A new study detailed all the problems with plans to shoot a missile out of the sky.
gizmodo.com
Israel’s Iron Dome has done a great job shooting down Hamas rockets and Iranian missiles. It’s also covering a small territory and shooting down projectiles that aren’t moving as fast as a nuclear weapon or a Russian Kh-47M2 Kinzhal ballistic missile might. The pitch of the Golden Dome is that it would keep the whole of the continental U.S. safe. That’s a massive amount of territory to cover and the system would need to identify, track, and destroy nuclear weapons, drones, and other objects moving at high speed.
That’s like trying to shoot a bullet out of the sky with a bullet. The missile defense study,
published on March 3, detailed a few of the challenges facing a potential Golden Dome-style system.
Trump’s executive order is vague and covers a lot of potential threats. “We focus on the fundamental question of whether current and proposed systems intended to defend the United States against nuclear-armed [intercontinental ballistic missile] now effective, or could in the near future be made effective in preventing the death and destruction that a successful attack by North Korea on the United States using such ICBMs would produce.”
Stopping a nuke is the primary promise of a missile system. And if one of these systems can’t stop a nuke then of what use is it?
The study isn’t positive. “This is the most comprehensive, independent scientific study in decades on the feasibility of national ballistic missile defense. Its findings may shock Americans who have not paid much attention to these programs,” Joseph Cirincione told Gimzodo.
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The study looked at a few different methods for knocking a North Korean nuke out of the sky. An ICBM launch has three phases: the boost phase which lasts only a few minutes, the midcourse phase which lasts around 20 minutes, and the terminal phase which is less than a minute.
During the boost-phase, the nuke is building up speed and getting into the air. “Boost-phase intercept of ICBMs launched from even a small country like North Korea is challenging,” the study said.
You have to get weapons close to the missile and, in the case of North Korea, that would require building them close to China and then firing them over Chinese territory. Any defense system would only have a few moments to respond to the nuke because the boost phase only lasts a few minutes.
For a countermeasure to hit that ICBM under those time constraints means it would need to be built close, probably somewhere in the Pacific. And we would need a lot of them. China would not be happy about a ring of missile defense systems close to its borders, no matter how America tried to sell it to them.
But what about space-based systems? It’s a territory rivals have less power over. “The scientific review panel found that it would take over a thousand orbiting weapons to counter a single North Korean ballistic missile. Even then, ‘the system would be costly and vulnerable to anti-satellite attacks,’” Cirincione told Gizmodo. Around 3,600 interceptors, to be precise.
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Well, what about lasers? Reagan’s original plan was lasers. Surely technology has advanced since the 1980s. “There is widespread agreement that laser weapons that could disable ICBMs during their boost-phase, whether based on aircraft, drones, or space platforms, will not be technically feasible within the 15-year time horizon of this study,” the study said.
This hints at another one of the problems of missile defense: it takes a long time to build and your enemies aren’t stagnant while it’s happening. While America works on the Golden Dome, Russia, North Korea, and China will be building their own new and different kinds of weapons meant to circumvent it. We may be able to build lasers capable of shooting nukes out of the sky in two decades but by then America’s enemies may have things to deal with the lasers.
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