The right dome for America

Strobe Talbott Center for Security, Strategy, and Technology

斯特罗布塔尔博特安全、战略和技术中心

Without giving many details, the Trump administration has proposed a robust, multitiered “Golden Dome” system to defend the United States against possible missile or aerial attack.

特朗普政府没有透露太多细节，但提出了一个强大的、多层的“金顶”系统，以保护美国免受可能的导弹或空袭。

The Congressional Budget Office (CBO) has estimated that such a system might cost $1.2 trillion to develop, deploy, and operate over 20 years.

美国国会预算办公室 (CBO) 估计，这样一个系统在 20 年内的开发、部署和运营可能需要花费 1.2 万亿美元。

But such a massive system would not only verge on unaffordable; it could cause an arms race without providing the actual protection it promises.

但如此庞大的系统不仅难以承受，而且还难以承受。它可能会在不提供其承诺的实际保护的情况下引发军备竞赛。

President Donald Trump is right that the nation has many technologies it did not possess when Ronald Reagan announced his Strategic Defense Initiative 43 years ago.

唐纳德·特朗普总统说得对，美国拥有许多 43 年前罗纳德·里根宣布战略防御计划时所不具备的技术。

But the laws of physics still dramatically challenge and constrain what a missile defense system might realistically achieve.

但物理定律仍然极大地挑战和限制了导弹防御系统可能实际实现的目标。

Instead of such a huge system emphasizing space-based interceptors, the United States might therefore consider a more modest system designed to deal with limited, unauthorized, accidental, or coercive attack scenarios.

因此，美国可能会考虑建立一个更温和的系统，以应对有限的、未经授权的、意外的或强制性的攻击场景，而不是建立一个强调天基拦截器的庞大系统。

We might forgo space-based interceptors, at least for now, and build something like a scaled-back version of the ground-based missile defense systems that the CBO postulated, designed to handle up to several dozen incoming warheads.

我们可能会放弃天基拦截器，至少目前如此，并建造类似美国国会预算办公室假设的陆基导弹防御系统的缩小版，旨在处理多达数十枚来袭弹头。

Adding the associated sensors, many of them based in space, the cost might be $200 billion to $300 billion over 20 years.

添加相关传感器（其中许多位于太空），20 年内的成本可能达到 2000 亿至 3000 亿美元。

Not since the Manhattan Project has a military program of such scale, with such potential implications for international security, been shrouded in such secrecy.

自曼哈顿计划以来，还没有一个如此规模、对国际安全具有如此潜在影响的军事计划被如此保密。

In January 2025, President Donald Trump issued an executive order calling for a multilayered nationwide protective shield against any and all airborne threats.

2025 年 1 月，唐纳德·特朗普总统发布了一项行政命令，呼吁在全国范围内建立多层防护罩，抵御任何和所有空中威胁。

He initially called the system “Iron Dome for America,” invoking the Israeli air and missile defense system that has proved so effective over the last three years.

他最初将该系统称为“美国的铁穹”，引用了以色列的防空和导弹防御系统，该系统在过去三年中被证明非常有效。

Today, it is known as the Golden Dome, after the president’s favorite color.

如今，它被称为金顶，以总统最喜欢的颜色命名。

Trump told the nation that the system would realize Ronald Reagan’s “Star Wars” vision of rendering nuclear weapons “ impotent and obsolete ” through modern technologies.

特朗普告诉全国，该系统将实现罗纳德·里根的“星球大战”愿景，即通过现代技术使核武器“无能为力且过时”。

Yet Trump then forbade the Pentagon from discussing specifics and has provided few details about the system.

然而，特朗普随后禁止五角大楼讨论具体细节，并且几乎没有提供有关该系统的细节。

That remains the case today.

今天仍然如此。

The Congressional Budget Office, interpreting what Trump’s directive might imply, recently developed a plausible architecture and estimated its cost at a whopping $1.2 trillion over 20 years.

国会预算办公室解释了特朗普的指令可能意味着什么，最近制定了一个看似合理的架构，并估计其 20 年内的成本高达 1.2 万亿美元。

Even more remarkably, the CBO’s notional system, and particularly its space-based interceptor boost-phase layer, was sized to only defend against 10 long-range missiles launched simultaneously from a single location.

更值得注意的是，国会预算办公室的概念系统，特别是其天基拦截弹助推层，其规模只能防御从一个地点同时发射的 10 枚远程导弹。

The hypothetical defensive architecture consisted of four tiers: one in space and three on land, each designed to address incoming missiles or warheads at a different phase of flight.

假设的防御架构由四层组成：一层在太空，三层在陆地，每一层都旨在应对不同飞行阶段的来袭导弹或弹头。

The highest-altitude land-based layer would build on the existing Alaska-centered system, adding more capable interceptors and two additional sites in the United States.

最高海拔的陆基层将建立在现有的以阿拉斯加为中心的系统的基础上，增加更多能力的拦截器和美国的两个额外站点。

A second, lower-altitude but still wide-area layer would also be based in the United States and would be designed to intercept hypersonic maneuvering missiles that the higher-altitude system could not address.

第二个低空但仍是广域的防空系统也将设在美国，旨在拦截高空系统无法拦截的高超音速机动导弹。

Four sites would be established across the continental 48 states for this purpose.

为此，将在大陆 48 个州建立四个站点。

The lowest-altitude layer would consist of roughly 35 regional sites designed to defend against threats such as cruise missiles.

最低高度层将由大约 35 个区域站点组成，旨在防御巡航导弹等威胁。

These sites would also provide a final chance to intercept hypersonic missiles that penetrated the previous layers, as well as warheads that, perhaps aided by accompanying decoys, had evaded them.

这些地点还将提供拦截穿透前几层的高超音速导弹以及可能在附带诱饵的帮助下躲避的弹头的最后机会。

Each of these more than 40 ground-based sites would have dedicated sensors and anywhere from several dozen to roughly 100 interceptor missiles, with the types of interceptors varying according to their chief purpose and expected target.

这 40 多个地面站点中的每一个都拥有专用传感器和数十到大约 100 枚拦截导弹，拦截导弹的类型根据其主要用途和预期目标而有所不同。

Short-range drones launched from within the United States or just over its borders would be handled separately through site defenses rather than national-level, wide-area systems.

从美国境内或越过其边境发射的短程无人机将通过站点防御而不是国家级广域系统单独处理。

Such defenses would be deployed especially around critical infrastructure or sites requiring dedicated protection, including those locations associated with national leadership.

此类防御将特别部署在需要专门保护的关键基础设施或地点周围，包括与国家领导层相关的地点。

Russia and China have hundreds of missiles, and China’s arsenal is growing fast.

俄罗斯和中国拥有数百枚导弹，中国的武库正在快速增长。

With similar assumptions, a full-bore defense designed to address an all-out nuclear attack could quite plausibly reach multiple trillions of dollars over that time period.

根据类似的假设，旨在应对全面核攻击的全面防御在这段时间内可能会达到数万亿美元。

The Republican-controlled Congress has so far funded Golden Dome without subjecting it to serious oversight or demanding information about the system, with the administration seeking an average of about $15 billion a year over the next five years.

到目前为止，共和党控制的国会为金圆顶提供了资金，但没有对其进行严格的监督，也没有要求提供有关该系统的信息，政府寻求在未来五年内平均每年提供约 150 亿美元的资金。

The Pentagon claims the whole thing can be deployed for $185 billion , but no one outside the Trump administration knows what that would entail.

五角大楼声称整个项目的部署需要 1850 亿美元，但特朗普政府之外没有人知道这会带来什么。

The American public deserves, and Congress should demand, a much fuller and more public debate.

美国公众应该、国会也应该要求进行更全面、更公开的辩论。

In fact, there is a good case for expanding air and missile defenses beyond the current limited capability , which is designed primarily to counter a North Korean threat and based largely in Alaska, with some 44 long-range interceptors of uncertain capability.

事实上，有一个很好的理由来扩大空中和导弹防御系统，使其超出目前的有限能力，该防御系统主要是为了应对朝鲜威胁，主要基地位于阿拉斯加，拥有约 44 个能力不确定的远程拦截器。

North Korea’s own growing capabilities, China’s major nuclear expansion, Russia’s and China’s development of hypersonic missiles and other more complex threats, and the proliferation of drone technology all argue for doing so.

朝鲜自身不断增长的能力、中国的重大核扩张、俄罗斯和中国开发高超音速导弹和其他更复杂的威胁，以及无人机技术的扩散都支持这样做。

And led by General Michael Guetlein at the Pentagon’s Office of Golden Dome for America, along with the Missile Defense Agency, the Space Force, the other military services, government-owned weapons labs, and the American defense industry, lots of smart people are pursuing lots of promising ideas.

在五角大楼美国金顶办公室的迈克尔·盖特兰将军的领导下，与导弹防御局、太空军、其他军事部门、政府拥有的武器实验室和美国国防工业一起，许多聪明人正在追求许多有前途的想法。

But Trump’s original directive to build a robust national defense against even an all-out nuclear attack is literally pie in the sky—simply not doable.

但特朗普最初的指令是建立强大的国防，甚至抵御全面的核攻击，这实际上是天上掉下来的馅饼——根本不可行。

We need a much more credible and transparent determination of what can be achieved, how, over what period, and at what cost.

我们需要更加可信和透明地确定可以实现什么、如何实现、在什么时期内以及以什么成本实现。

The idea of building defenses against long-range missiles has been around for decades, almost as long as the long-range missiles themselves.

建立针对远程导弹的防御系统的想法已经存在了数十年，几乎与远程导弹本身一样长。

But the 1972 Anti-Ballistic Missile (ABM) Treaty between Moscow and Washington was built on the assessment that the large-scale deployment of missile defenses would likely fuel an offense-defense arms race.

但 1972 年莫斯科和华盛顿签署的《反弹道导弹条约》是基于这样的评估：大规模部署导弹防御系统可能会加剧攻防军备竞赛。

The defenses of the day were seen as unlikely to work well enough to afford meaningful protection, yet credible enough that each side would fear the other’s defenses and undertake even larger offensive arms buildups to ensure a viable deterrent.

当时的防御措施被认为不太可能发挥作用，无法提供有意义的保护，但又足够可信，以至于双方都会害怕对方的防御，并进行更大规模的进攻性军备建设，以确保可行的威慑力。

A vicious action-reaction cycle would ensue, leaving no one safer and everyone poorer.

随之而来的是一种恶性的行动-反应循环，没有人更安全，每个人都更穷。

As such, the treaty wound up limiting each side to one major defense site, which the Soviet Union elected to deploy around its capital.

因此，该条约最终将双方限制在一个主要防御地点，苏联选择将其部署在其首都周围。

The United States, seeing little point in trying to shield itself against approximately 10,000 long-range Soviet warheads with the day’s available technologies, soon lost interest in deploying even that single site.

美国认为，利用当时可用的技术来防御大约 10,000 枚苏联远程弹头没有什么意义，因此很快就失去了部署单一站点的兴趣。

Reagan’s Strategic Defense Initiative (SDI) did not change the situation very much in the end—but the end of the Cold War did.

里根的战略防御计划（SDI）最终并没有使局势发生太大变化，但冷战的结束却改变了这一局面。

As a result, President George W.

结果，乔治·W·布什总统

Bush withdrew from the ABM Treaty in 2002.

布什于2002年退出《反导条约》。

The United States proceeded to deploy a limited system on the West Coast, with interceptors in Alaska and California and detection and tracking radars at various locations on land and sea.

美国开始在西海岸部署有限的系统，在阿拉斯加和加利福尼亚州部署拦截器，并在陆地和海上多个地点部署探测和跟踪雷达。

Space-Based Infrared System (“SBIRS”) satellites would cue the system by detecting the hot plumes of the boosting missiles.

天基红外系统（“SBIRS”）卫星将通过检测助推导弹的热羽流来向系统发出信号。

The system was sized and located to intercept North Korean missiles after they finished their burn or boost phases , when they would embark on roughly 20 minutes of ballistic, unpowered flight outside the atmosphere toward North America.

该系统的尺寸和位置是为了在朝鲜导弹完成燃烧或助推阶段后对其进行拦截，此时朝鲜导弹将在大气层外进行大约 20 分钟的弹道无动力飞行，飞向北美。

The interceptors are large, staged rockets that would carry a maneuvering exoatmospheric kill vehicle weighing some 140 pounds toward an incoming warhead, destroying it through the sheer force of the direct collision, without any explosive whatsoever.

这些拦截弹是大型分级火箭，可携带重约 140 磅的机动大气层外杀伤飞行器飞向来袭弹头，通过直接碰撞的巨大力量将其摧毁，而无需任何爆炸物。

Alas, while hit-to-kill interceptors are now proving their worth with the shorter-range Terminal High Altitude Area Defense, known as THAAD, Aegis/Standard Missile, and Patriot PAC-3 systems, it remains difficult to make the defense work at longer range and higher speed.

可惜的是，虽然命中杀伤拦截弹现在已经通过短程末端高空区域防御（萨德、宙斯盾/标准导弹和爱国者 PAC-3 系统）证明了自己的价值，但要让防御在更远的射程和更高的速度下发挥作用仍然很困难。

The Alaska-based system has succeeded in a bit more than half of its realistic tests against intercontinental ballistic missile-range targets, although its performance has been improving.

尽管其性能一直在提高，但基于阿拉斯加的系统在针对洲际弹道导弹射程目标的实际测试中已经成功了一半以上。

The tests did not, however, include the types of countermeasures one might expect a real adversary to employ—notably, large numbers of decoys mimicking real warheads within a given “threat cloud.”

然而，这些测试并未包括人们可能期望真正的对手采用的对策类型，特别是在给定的“威胁云”内模仿真实弹头的大量诱饵。

Reagan’s 1983 “Star Wars” speech envisioned space-based defenses that would add remarkable new capabilities, far beyond even what the United States deploys today, to defeat the Soviet nuclear threat.

里根 1983 年的“星球大战”演讲设想了天基防御，它将增加非凡的新能力，甚至远远超出美国今天部署的能力，以击败苏联的核威胁。

Although the SDI program was later largely discredited as a plausible system, it did persuade Soviet leaders they could not win an offense-defense arms race with America, thus contributing to the end of the Cold War .

尽管战略防御计划后来在很大程度上被认为是一个看似合理的体系，但它确实说服了苏联领导人，他们无法赢得与美国的攻防军备竞赛，从而为冷战的结束做出了贡献。

It also produced some of the technologies that have helped protect Ukraine, Israel, and America’s Persian Gulf allies in recent years.

它还生产了一些近年来帮助保护乌克兰、以色列和美国波斯湾盟友的技术。

Trump now claims that, four decades later, the United States has the technologies to pursue Reagan’s previously elusive dream.

特朗普现在声称，四十年后，美国拥有实现里根先前难以实现的梦想的技术。

Trump is not all wrong about the progress.

特朗普对进展的看法并不完全错误。

There are very impressive new technologies, beyond the hit-to-kill technology developed over the last 30 years.

除了过去 30 年开发的击杀技术之外，还有令人印象深刻的新技术。

For example, the so-called Hypersonic and Ballistic Tracking Space Sensor satellites will offer much more precise coordinates for any threatening object headed toward the United States.

例如，所谓的高超音速和弹道跟踪空间传感器卫星将为任何前往美国的威胁物体提供更精确的坐标。

It may also be possible to put interceptors in space that could remain in orbit for years until needed—although lasers are a different kettle of fish.

也有可能在太空中放置拦截器，这些拦截器可以在轨道上停留数年，直到需要为止——尽管激光是另一回事。

The advent of cheaper space launch has made a big difference too: it is now possible to imagine putting big numbers of large interceptor rockets into orbit relatively affordably.

更便宜的太空发射的出现也产生了很大的变化：现在可以想象以相对便宜的价格将大量大型拦截火箭送入轨道。

But as Steve Fetter and David Wright have convincingly argued, it is much harder to protect a huge country like the United States from concerted enemy action than a small country like Israel.

但正如史蒂夫·费特和大卫·赖特令人信服地指出的那样，保护像美国这样的大国免受敌人的一致行动比保护像以色列这样的小国要困难得多。

Even more to the point, it is much harder to effectively protect a large country against nuclear attack than conventional explosives: while a few defensive failures against conventional attack, however tragic, would not generally bring a country to its knees, even a single nuclear warhead getting through could amount to the single deadliest attack in a country’s history.

更重要的是，有效保护一个大国免受核攻击比使用常规爆炸物要困难得多：虽然针对常规攻击的一些防御失败，无论多么悲惨，通常不会使一个国家屈服，但即使是一颗核弹头穿过，也可能构成一个国家历史上最致命的一次攻击。

There are two other enduring realities, based on the immutable laws of physics more than the current and changing technologies of the day, that severely complicate any pursuit of a robust large-scale air and missile defense system.

还有另外两个持久的现实，它们基于不可改变的物理定律，而不是当今不断变化的技术，这使得对强大的大规模防空和导弹防御系统的追求变得严重复杂化。

First is the problem of decoys.

首先是诱饵的问题。

Because space is a (near) vacuum, objects accelerated there to a given speed will continue to move at the same speed regardless of their size, shape, or weight.

由于太空是（接近）真空，因此加速到给定速度的物体将继续以相同的速度移动，无论其大小、形状或重量如何。

Hence, a light decoy, say a Mylar balloon designed to reflect radar waves, with a small heating device inside to mimic the heat signature of a real warhead, will be difficult to distinguish from a real threat.

因此，光诱饵，例如设计用来反射雷达波的聚酯薄膜气球，内部有一个小型加热装置来模仿真实弹头的热信号，将很难与真正的威胁区分开来。

In theory, one can shine a particle beam at the different objects to try to identify them—but that requires proximity and lots of power.

理论上，人们可以将粒子束照射到不同的物体上来尝试识别它们，但这需要接近度和大量的能量。

Second is a stark reality about objects in low-Earth orbit, which is where space-based interceptors would need to operate: the so-called “absentee ratio.” At any given moment, most space-based interceptors would be out of position to destroy a particular intercontinental ballistic missile (ICBM).

其次是近地轨道物体的严峻现实，这是天基拦截器需要运行的地方：所谓的“缺席率”。在任何特定时刻，大多数天基拦截弹都无法摧毁特定的洲际弹道导弹（ICBM）。

Since they are constantly moving relative to the Earth’s surface, they cannot hover over a possible launch point.

由于它们相对于地球表面不断移动，因此无法悬停在可能的发射点上空。

And because an attacker could launch an ICBM at any moment, an effective defense would require flooding low-Earth orbit with interceptors to create a lattice that would always have some interceptors in the right place at the right time.

由于攻击者可以随时发射洲际弹道导弹，因此有效的防御需要在近地轨道上布满拦截器，以创建一个网格，在正确的时间、正确的地点始终有一些拦截器。

This absentee ratio is often very high.

这种缺勤率往往非常高。

The CBO calculates that, if the goal of interceptors is to destroy an ICBM in the boost phase before any decoys could be deployed, the absentee ratio for interceptors using current technology would be about 390:1.

美国国会预算办公室计算出，如果拦截弹的目标是在部署任何诱饵之前摧毁助推阶段的洲际弹道导弹，那么使用当前技术的拦截弹的缺席率约为 390:1。

Assuming two shots per incoming missile, the CBO calculates that 7,800 space-based interceptors would be required to have a good chance of destroying 10 ICBMs.

假设每枚来袭导弹发射两枚，国会预算办公室计算出需要 7,800 个天基拦截器才能有很大机会摧毁 10 枚洲际弹道导弹。

At more than $20 million per interceptor, that would cost more than $700 billion over 20 years, since the satellites would likely last only about five years each.

如果每颗拦截器的成本超过 2000 万美元，那么 20 年内的成本将超过 7000 亿美元，因为每颗卫星的使用寿命可能只有大约五年。

Slight atmospheric drag at the altitudes in question would gradually degrade their orbits.

在相关高度上轻微的大气阻力会逐渐降低它们的轨道。

Over two decades, therefore, the United States would need to build and launch some 30,000 satellites—that is, replenishing the original constellation three times.

因此，在二十年的时间里，美国需要建造和发射约 30,000 颗卫星，也就是说，将原来的星座补充三倍。

The absentee ratio would be much lower if the space-based interceptors were designed to shoot down threats during their midcourse flight rather than their much shorter boost phase—20 minutes versus three to five.

如果天基拦截弹的设计目的是在中途飞行期间击落威胁，而不是缩短助推阶段（20 分钟而不是三到五分钟），那么缺席率就会低得多。

Depending on interceptor speed, the ratio might be 10:1 or less .

根据拦截器速度，该比率可能为 10:1 或更小。

But that brings us back to the decoy problem: during midcourse, warheads are difficult to distinguish from objects designed to mimic them.

但这又让我们回到了诱饵问题：在中途，很难将弹头与旨在模仿它们的物体区分开来。

In theory, a nuclear warhead on the interceptor could destroy an entire threat cloud, but the resulting radiation would fry a lot of the satellite electronics needed to track and target subsequent threats.

理论上，拦截器上的核弹头可以摧毁整个威胁云，但由此产生的辐射会烧毁跟踪和瞄准后续威胁所需的大量卫星电子设备。

Other approaches, including electronic warfare or conventional explosives that disperse shrapnel, might take out much or most of a threat cloud, but the distances involved make such approaches highly challenging.

其他方法，包括电子战或散布弹片的常规爆炸物，可能会消除大部分或大部分威胁云，但所涉及的距离使此类方法极具挑战性。

Historically, the consensus has usually been that countermeasures are relatively simple to deploy and difficult to defeat.

从历史上看，人们通常认为反措施相对容易部署且难以击败。

Major nuclear powers have already perfected technologies to disperse multiple objects—including multiple independently targetable reentry vehicles—from a single missile “bus,” and similar decoys could considerably complicate missile defense.

主要核大国已经完善了从单个导弹“总线”上分散多个物体（包括多个可独立瞄准的再入飞行器）的技术，而类似的诱饵可能会使导弹防御变得相当复杂。

Nuclear weapons are not going to become impotent and obsolete anytime soon, if ever.

核武器不会很快变得无效和过时（如果有的话）。

But more modest homeland missile defenses could play several useful roles.

但更温和的本土导弹防御系统可以发挥一些有用的作用。

(I am assuming, as did the CBO, that defenses against short-range drones launched from within or next to American territory will remain a separate proposition, best handled locally and perhaps not by the Department of Defense.) Think of it less as a golden dome than a bronze one, perhaps.

（我和国会预算办公室一样，假设防御从美国境内或附近发射的短程无人机仍将是一个单独的提议，最好在当地处理，也许不是由国防部处理。）也许，与其将其视为金色圆顶，不如将其视为青铜圆顶。

One worthy goal would be to defend against a small attack by North Korea or, someday perhaps, Iran with higher confidence than is the case today.

一个有价值的目标是比今天更有信心地抵御朝鲜或伊朗（也许有一天）的小规模袭击。

Combining defensive capabilities with the capacity to conduct preemptive strikes prior to an ICBM launch, or cyberattacks against the electronics used by such offensive weapons, may be enough to thwart these threats even as they improve and expand.

将防御能力与在洲际弹道导弹发射之前进行先发制人打击的能力相结合，或对此类进攻性武器使用的电子设备进行网络攻击，可能足以阻止这些威胁，即使它们有所改善和扩大。

A limited national missile defense system could also provide some protection against a possible accidental or unauthorized launch, perhaps one initiated by a rogue commander of a given missile silo or submarine.

有限的国家导弹防御系统还可以提供一些保护，防止可能的意外或未经授权的发射，可能是由特定导弹发射井或潜艇的流氓指挥官发起的。

Such a capability might also prove useful, heaven forbid, if a rogue AI system launches a nuclear attack—even though the United States and China have already agreed that AI should never be given the authority to launch a nuclear war.

如果一个流氓人工智能系统发动核攻击，这种能力也可能被证明是有用的——尽管美国和中国已经同意人工智能永远不应该被授予发动核战争的权力。

A limited missile defense could also help in certain great-power war scenarios and, one hopes, help deter them in the first place.

有限的导弹防御系统也有助于应对某些大国战争场景，并且人们希望能够从一开始就阻止它们。

For example, if China were losing a fight over Taiwan, it might be tempted to roll the dice by detonating a nuclear warhead high above a single U.S. military base.

例如，如果中国在台湾问题上输掉了一场战斗，它可能会想通过在单个美国军事基地上空引爆核弹头来掷骰子。

The goal could be partly to shut down American military capabilities there while causing only modest loss of civilian life, if the location were chosen correctly.

如果地点选择正确的话，其目标可能部分是关闭美国在那里的军事能力，同时只造成适度的平民生命损失。

Such an attack would also seek to put the fear of God into an American president in the hope that he or she would seek to end the war before it escalated further.

这样的攻击还将试图让美国总统敬畏上帝，希望他或她能够在战争进一步升级之前寻求结束战争。

It would be a very high-risk gamble, to be sure.

可以肯定的是，这将是一场风险极高的赌博。

But a desperate Chinese leader might not rule out the idea, rather than lose Taiwan and quite likely their own hold on power.

但绝望的中国领导人可能不会排除这个想法，而不是失去台湾，而且很可能失去自己的权力。

Certainly, the history of American nuclear brinkmanship—from Korea to Taiwan to Berlin to Cuba to the Middle East—implies that such threats cannot simply be dismissed.

当然，美国核边缘政策的历史——从韩国到台湾、柏林、古巴再到中东——意味着不能简单地忽视这种威胁。

Vladimir Putin’s behavior and threats early in the Ukraine war suggest the same.

弗拉基米尔·普京在乌克兰战争初期的行为和威胁也表明了这一点。

Missile defenses could complicate or deny such an option to a future adversary decisionmaker.

导弹防御可能会使未来对手决策者的这种选择变得复杂或无法实现。

They could also help fend off attacks by long-range, conventionally armed ICBMs if a future China or Russia attempted to use them to destroy several key military bases.

如果未来中国或俄罗斯试图使用远程常规洲际弹道导弹摧毁多个关键军事基地，它们还可以帮助抵御远程常规洲际弹道导弹的攻击。

In that case, even imperfect defenses could work to the defender’s advantage by denying a would-be attacker any confidence that such a limited strike would achieve its objectives.

在这种情况下，即使是不完美的防御也可以让潜在的攻击者对这种有限的攻击能够实现其目标失去信心，从而对防御者有利。

There is another reason defenses might appeal at a broader strategic level.

防御可能在更广泛的战略层面上具有吸引力还有另一个原因。

Historically, as noted before, they have been viewed as a potential catalyst to an arms race.

从历史上看，如前所述，它们被视为军备竞赛的潜在催化剂。

In the future, however, they could help discourage one by providing an alternative to an offense-only nuclear arms race.

然而，在未来，它们可以通过提供一种替代仅限进攻性的核军备竞赛的方式来帮助阻止人们这样做。

U.S. intelligence now projects that China will deploy 1,000 to 1,500 nuclear warheads in the 2030s, up from just 200 a few years ago and about 600 today.

美国情报机构目前预测，中国将在 2030 年代部署 1,000 至 1,500 枚核弹头，而几年前仅为 200 枚，如今约为 600 枚。

Once that happens, traditional bilateral arms control, already on life support at best, will likely be dead.

一旦发生这种情况，传统的双边军备控制（充其量已经靠生命维持）很可能会消亡。

China and Russia are not really allies, and so they will refuse to have their aggregate arsenals limited to the same ceiling as America’s, leaving the United States as nuclear superpower No. 1.

中国和俄罗斯并不是真正的盟友，因此他们将拒绝将其核武库总量限制在与美国相同的上限，从而使美国成为第一核超级大国。

But the United States will not accept a world in which China and Russia are each allowed arsenals the same size as its own, creating three nuclear superpowers with two aligned against it.

但美国不会接受这样一个世界：中国和俄罗斯都拥有与自己同等规模的核武库，从而形成三个核超级大国，两个超级大国与之结盟。

(The arsenals of Britain and France are much smaller.) Rather than try to match the combined Chinese and Russian arsenals and risk an arms race, the United States might better sustain parity through a blend of offensive and defensive capabilities.

（英国和法国的核武库要小得多。）美国最好通过进攻和防御能力的结合来维持平衡，而不是试图与中国和俄罗斯的核武库相抗衡并冒着军备竞赛的风险。

It would likely have a certain advantage in defenses, while Moscow and Beijing together would have the combined edge in offensive nuclear weapons.

它可能在防御方面具有一定优势，而莫斯科和北京在进攻性核武器方面将拥有综合优势。

Everyone, however, would still have enough weapons to wreak unimaginable havoc.

然而，每个人仍然拥有足够的武器来造成难以想象的破坏。

With the kind of transparency measures that Amy Nelson and I have previously advocated, a stable three-way equilibrium might be reached.

通过艾米·纳尔逊和我之前倡导的透明度措施，可能会达到稳定的三向平衡。

A partial model for what might make sense was presented by the first Bush administration in the early 1990s.

20 世纪 90 年代初，第一届布什政府提出了一个可能有意义的部分模型。

Named GPALS , for the Global Protection Against Limited Strikes system, it was designed to shoot down up to about 200 incoming warheads—though that was probably a very optimistic estimate of how many warheads it could actually have handled.

它被命名为 GPALS，代表“全球有限打击防护系统”，其设计目的是击落多达约 200 枚来袭弹头——尽管这可能是对其实际可处理弹头数量的非常乐观的估计。

In theory, it would have used land-based interceptors at some six sites around the country, along with 1,000 space-based interceptors.

理论上，它会在全国大约六个地点使用陆基拦截器，以及 1,000 个天基拦截器。

A second phase could have added more of everything.

第二阶段可能会增加更多的东西。

With only 1,000 space-based interceptors instead of 30,000, the system became affordable even with the technological constraints of the day: about $150 billion in 2026 dollars, or roughly one-eighth of what the CBO’s interpretation of Golden Dome might amount to, despite being sized against a larger enemy threat.

由于只有 1,000 个天基拦截器而不是 30,000 个，即使在当时的技术限制下，该系统也变得可以负担得起：按 2026 年美元计算，该系统的成本约为 1,500 亿美元，大约是国会预算办公室对金顶的解释的八分之一，尽管该系统的规模是针对更大的敌人威胁的。

Rather than attempt to build something like GPALS that included a large space-based system, we might build something like a scaled-back version of the three-tiered, ground-based missile defense systems that CBO postulated, designed to handle up to several dozen incoming warheads.

我们可能不会尝试建造类似包含大型天基系统的 GPALS 之类的东西，而是可能会建造类似 CBO 所假设的三层陆基导弹防御系统的缩小版，旨在处理多达数十枚来袭弹头。

If a major U.S. adversary concentrated a large attack on one part of the country, it could, in theory, saturate the defenses, thereby maintaining a viable deterrent without engaging in an all-out arms race.

如果美国的主要对手集中对美国的一个地区进行大规模攻击，理论上来说，它可以使防御饱和，从而在不进行全面军备竞赛的情况下保持可行的威慑力。

Indeed, it could likely do so without keeping its nuclear forces on hair-trigger alert.

事实上，它很可能在不保持核力量一触即发的戒备状态的情况下做到这一点。

By contrast, if the United States deployed very large defenses, an adversary might fear an American preemptive attack against its nuclear forces that would eliminate much of its deterrent, with U.S. defenses mopping up the rest.

相比之下，如果美国部署了非常庞大的防御系统，对手可能会担心美国对其核力量进行先发制人的攻击，这将消除其大部分威慑力，而美国的防御系统会消灭其余部分。

It might then feel compelled either to enlarge its offensive forces, maintain a launch-on-warning posture, or both.

然后，它可能会感到有必要要么扩大进攻力量，要么保持警告后发射的姿态，要么两者兼而有之。

On balance, there is a promising chance that a limited, three-tiered, ground-based defense architecture assisted by sensors on Earth and in space could offer defenses against various forms of accidental, unauthorized, or rogue-state attack without compromising strategic stability.

总而言之，在地球和太空传感器的协助下，有限的三层地面防御架构很有可能在不损害战略稳定性的情况下防御各种形式的意外、未经授权或流氓国家攻击。

Any space-based interceptors that the United States chose to deploy might focus just on warheads in midcourse flight, since the absentee ratio would be much less than for boost-phase defense.

美国选择部署的任何天基拦截弹都可能只关注中途飞行的弹头，因为缺席率将远低于助推阶段防御。

But again, I am skeptical of even that approach, since decoys would likely be able to overwhelm such a space-based midcourse system.

但我再次对这种方法表示怀疑，因为诱饵很可能能够压倒这样的天基中段系统。

Ground-based interceptors coupled with ground-based and space-based sensors seem to be the sounder approach.

地基拦截器与地基和天基传感器相结合似乎是更合理的方法。

Adding the associated sensors, many of them based in space, the price tag would remain below $500 billion over 20 years, according to the CBO’s estimates.

根据 CBO 的估计，加上相关的传感器（其中许多传感器位于太空），其价格在 20 年内将保持在 5000 亿美元以下。

Indeed, if the system were designed to shoot down perhaps several dozen warheads and thus scaled back considerably from what the CBO assumes, the cost might wind up closer to $200 billion to $300 billion—roughly 2% of the likely average annual defense budget over the next two decades.

事实上，如果该系统的设计目的是击落大约数十枚弹头，从而大大低于国会预算办公室的假设，那么成本可能会接近 2000 亿至 3000 亿美元，大约相当于未来二十年平均年度国防预算的 2%。

If boost-phase defense is desired against North Korea, there are other options, given the Korean Peninsula’s geography.

考虑到朝鲜半岛的地理位置，如果需要对朝鲜进行加强阶段的防御，还有其他选择。

Specifically, aircraft based in Japan, manned or unmanned, could field interceptor missiles using relatively straightforward technology to shoot down North Korean ICBMs during their roughly five minutes of boosted flight—when the missiles would present large, unitary targets because decoys could not yet have been deployed.

具体来说，驻扎在日本的有人或无人飞机可以使用相对简单的技术部署拦截导弹，在大约五分钟的助推飞行期间击落朝鲜洲际弹道导弹——此时导弹将瞄准大型单一目标，因为诱饵尚未部署。

Jaganath Sankaran and Steve Fetter estimate that such a system could be built and operated for no more than several hundred million dollars a year in development, procurement, and operating costs, assuming a system made up of perhaps several dozen interceptors.

贾加纳特·桑卡兰（Jaganath Sankaran）和史蒂夫·费特（Steve Fetter）估计，假设系统由几十个拦截器组成，那么每年建造和运行此类系统的开发、采购和运营成本不会超过数亿美元。

These are systems worth researching and analyzing, discussing with allies and eventually the Russians and Chinese, and perhaps deploying.

这些系统值得研究和分析，与盟友讨论，最终与俄罗斯和中国讨论，也许还值得部署。

But it cannot happen just within the halls of the Pentagon.

但这不可能只发生在五角大楼的大厅内。

It is time for the Trump administration to explain itself, lay out its concepts and initial plans for a national air and missile defense system, and bring the rest of us into the debate.

现在是特朗普政府自我解释的时候了，阐述其国家防空和导弹防御系统的概念和初步计划，并让我们其他人参与辩论。

After all, Article I of the Constitution gives the Congress—the people’s branch of government—power of the purse over the nation’s armed forces.

毕竟，宪法第一条赋予国会——人民政府部门——对国家武装部队的财政权。