America vs. Russia: Will Missile Defense Help in a Global Nuclear War?
The intensity of relations between the United States and Russia has reached its zenith. That has led nuclear deterrence and missile defense to once again become a relevant subject of discussion, as they were during the Cold War. I have already discussed the countries’ balance of strategic nuclear forces in a separate series of articles covering land, undersea and air components. Now it's time to pay attention to their missile-defense system capabilities and assess whether they can—at this point or in the future—shift the strategic balance towards any party’s side.
U.S. Missile Defense: Strategic GMD and Progressive Aegis
The only existing U.S. strategic missile-defense system capable of intercepting the warheads of intercontinental ballistic missiles is GMD (Ground-Based Midcourse Defense). The principle of the system is the kinetic interception of enemy warheads prior to their entry into the atmosphere. The target is destroyed by a direct hit with a small Exoatmospheric Kill Vehicle (EKV) interceptor, which is sent to the enemy warhead by the Ground-Based Interceptor (GBI) launch vehicle. The top speed to which EKV accelerates is approximately ten kilometers per second, and the speed of an ICBM warhead is approximately seven kilometers per second. Direct head-on collision at such speeds leads to the guaranteed complete destruction of any combat unit. However, the most difficult task in this situation is to successfully lock the kinetic interceptor on a target moving at great speed. At this point, eighteen test interceptions using the GMD system have been performed, with nine being successful—only 50 percent. This is despite the fact that tests are conducted in the most benign conditions; the target is known in advance and consists of a single warhead with no missile defense breaching systems. At this point, about thirty interceptors are deployed in Alaska and California, with the plan being to increase their number to forty-four by 2017. At this stage of development, GMD will be able to knock down at least twenty warheads in case of a large-scale ICBM strike. Considering that based on the New START Treaty, Russia and the United States may possess up to 1,550 strategic nuclear warheads, this figure is small and insignificant.
Another, more “flexible,” missile defense system, which may claim the label of strategic by 2022, is the Aegis Ballistic Missile Defense System, originally created in a ship-mounted modification. Now the land version—the Aegis Ashore—is being built in Romania and Poland. The Aegis BMD has a great advantage due to the placement of SM-3 missiles in the universal Mk-41 cell launchers. Not only is the Mk-41 compatible with interceptor missiles, it is also capable of launching anti-ship missiles and BGM-109 Tomahawk strategic cruise missiles. Currently the SM-3 Block IB interceptor missile is used, which is able to destroy short- and medium-range missiles at ranges of up to seven hundred kilometers. They are capable of intercepting ICBMs only at the initial stage of the flight, and given the size of Russia’s territory, and most underground missile silos and mobile units’ location far from Russia’s borders and seas, striking down the missiles at launch would be impossible. There are new versions of missiles, named the SM-3 Block IIA in development (phase-in expected in 2018) and the SM-3 Block IIB (phase-in planned for 2022). They dramatically outperform their predecessors in speed and range, which reaches 2,500 kilometers. Those new variants are likely to have the ability to destroy ICBMs warheads. In fact, they are very similar to GMD. In addition to missiles warfare, the Aegis has already proven that it is capable of effectively dealing with low-orbit satellites.
And yet, as we have already noted, the real effectiveness of ICBM warhead interception is yet very low, and initial flight-stage missile interception in the event of confrontation with Russia is inefficient (the European part of Russia holds a very small number of ICBMs—and in theory those are only possible to bring down during the launching phase). After the warhead has separated from the booster, it is practically impossible to intercept, and after separating the plurality of warheads and decoys too many interceptors are needed to repel the attack. And they are very expensive—more expensive than the warheads.
Russian Missile Defense: A-235 to Replace the A-135