Why The Pentagon's Missile Defense Plan Leaves The U.S. Unprotected From Russian Nuclear Attack
This is the day that President Trump unveils the Pentagon’s long-delayed plan for defending the United States against attack by missiles carrying nuclear warheads. If you think defense of the American homeland is a top military priority, consider this: the Pentagon currently spends ten times more propping up the tottering government of Afghanistan than it does protecting our nation from the one danger that could destroy the republic before sundown.
The new plan won’t change that anytime soon. Like the administration’s nuclear posture review released last year, it largely continues programs inherited from the Obama years, and doesn’t propose to counter the biggest nuclear threats the U.S. faces–at least, not with active defenses. That job is left to our offensive nuclear deterrent, which is supposed to dissuade countries like Russia and China from launching large-scale aggression by threatening overwhelming retaliation.
This may be the first time in history that a major military power has elected not to invest in extensive defenses against the biggest threat to its survival. The United States opted instead for a strategy that came to be known among experts as the “mutual hostage relationship,” in which America and Russia were both assured of the capability to wipe each other out. The thinking at the time the strategy was formalized was that nuclear weapons were simply too powerful to defeat using any known defensive technologies.
Ronald Reagan thought that the mutual hostage relationship was a disaster waiting to happen, and he proposed shifting emphasis to space-based defenses that could intercept Russia’s long-range ballistic missiles. However, no president after Reagan believed that was feasible or affordable, so America’s survival today depends on scaring opponents into avoiding nuclear aggression. The Pentagon spends most of its strategic budget on assuring that no matter what enemies might throw at us in a surprise attack, the U.S. can retaliate in ways unacceptable to the aggressor.
Unfortunately, Reagan was probably right about deterrence over the long run. Nothing lasts forever, including the “delicate balance of terror.” Some day, in some way, offensively-based deterrence will fail. Maybe the leaders of a major nuclear power will be crazy. Maybe they will be sane but prone to mistakes in crises. Maybe there will be a technical malfunction in their early warning system (that has already happened several times). The possibilities are endless, and so nuclear war remains the most likely way in which our civilization will end.
None of this is an argument against modernizing America’s aged nuclear triad. Until a better approach is within our grasp, Washington must do everything it can to convince potential aggressors that a nuclear attack would be suicidal. But we can’t assume that message will be received clearly or convincingly in places like Iran or North Korea, so the U.S. needs to invest in missile defenses to the extent they can be made to work.
The thinking reflected in the plan unveiled Thursday is that 30 years of modest investment in defensive technologies has gotten us to a point where we might be able to defeat a small, unsophisticated attack by countries like North Korea. If, for example, the U.S. constructs a defensive system with two layers of interceptors that attacking missiles must penetrate, and each layer is 80% effective, then in theory only one in 25 attacking warheads will reach their intended targets. North Korea probably doesn’t have that many warheads, and at the moment it can’t fit them on long-range missiles anyway.
In the case of Russia, though, there are over a thousand nuclear warheads aimed at America, and that’s not even counting all the shorter-range nuclear weapons that might be used to attack our allies and overseas troops. Nothing in the current U.S. defensive arsenal, or likely to be built in the near future, could cope with an attack on that scale. Even a few dozen incoming warheads would overwhelm the existing “ground-based midcourse defense” system, given the penetration aids and other features of a sophisticated attack. Like the Reagan plan, the Pentagon plan unveiled Thursday envisions space-based sensors and interceptor systems might improve the “cost-exchange” calculus between offense and defense, but that would take a decade or longer to implement.
Therein lies the biggest political obstacle to building robust homeland defenses. Political cycles are shorter than technology development cycles for complex defensive technologies, and every time a Republican administration tries to build something more effective a Democratic administration soon comes along to undercut it. The Democratic view generally is that arms control is more effective at reducing the nuclear threat than building defenses, and that any serious attempt to erect defenses will destabilize the nuclear balance by stimulating adversaries to buy more weapons.
This reasoning explains how policymakers backed into believing during the Cold War that Russia needed to be guaranteed the ability to wipe out America. It was the only way to stop Moscow from buying more nuclear weapons, and start talking seriously about reducing arsenals. The problem, of course, is that despite major reductions, both sides were left defenseless against the day that deterrence might somehow collapse (probably in a crisis). At that point, it would be lights out for American democracy – tens of millions would die, and the nation might never fully recover.
The most important question policymakers should be asking about missile defense today is whether three decades of technological progress since the Reagan years have provided the military with options for negating nuclear threats bigger than that posed by North Korea. Those options need to be viable not only against the current Russian arsenal, which consists overwhelmingly of ballistic missiles, but also against future weapons that might be added to circumvent defenses such as hypersonic systems. Missile defense experts call that the “responsive threat.”
The Trump Administration doesn’t know the answer. It believes it can cope with an Iranian or North Korean nuclear threat, but China and Russia will present much more potent challenges for the foreseeable future. A key feature of the Pentagon’s plan is to invest more heavily in space-based technologies that might make the tracking and interception of large numbers of warheads practical. Even if technical solutions are found, chances are that we and our children will remain hostages to the whims of our most powerful adversaries.