Inside The U.S. Missile Defense Agency's Secret Next Generation Interceptor
Get started on your Homeland Security Degree at American Military University.
Earlier this year, the Pentagon’s Missile Defense Agency determined that a planned upgrade to the nation’s defense against long-range North Korean missiles wasn’t going to work. A seeker essential to homing in on hostile nuclear warheads wasn’t suitable for operations in space, where the current U.S. homeland defense is designed to intercept attackers.
The upgrade program was canceled in August, and within weeks a draft solicitation for a Next Generation Interceptor was issued to industry. The solicitation described a much more capable system for negating North Korean attacks, specifying nearly 50 threat scenarios in which the new system would need to work effectively. Some of the scenarios involved demanding challenges that are not within the operational “envelope” of the existing defensive network.
The Missile Defense Agency has said very little of substance about the Next Generation Interceptor program, such as when it must be operational or how it will be configured. What follows is a simple explanation of the new system, based on conversations with half a dozen people who are conversant with the agency’s objectives.
It will be a hit-to-kill missile. The head of the missile agency told a think tank audience on Monday that “all options are being considered.” That is only true in a narrow sense. Nobody is seriously considering using a beam weapon to counter incoming ballistic warheads. The plan is to develop a new hit-to-kill system sitting on a new solid-rocket stack that can destroy hostile warheads with the sheer energy of impact. Conceptually, the Next-Generation Interceptor resembles the existing approach to homeland missile defense.
It will have multiple warheads. The single-warhead design of existing interceptors can be overwhelmed by a moderate number of attackers. The Missile Defense Agency envisions 64 interceptors total in the current system, with 2-4 allocated to each attacker depending on circumstances. That means a threat involving two dozen warheads, or even a handful of warheads accompanied by sophisticated decoys, might saturate the system. The plan for the Next Generation Interceptor is to stick with 64 interceptor missiles, but equip each interceptor with multiple kill vehicles that can counter a number of attackers.
It will fit in existing silos. The current homeland missile defense system concentrates its interceptors in underground silos at Fort Greely in Alaska (four more are deployed at Vandenberg Air Force Base in California). The plan is to expand the number of silos at Fort Greely from 40 to 60, and perhaps reach a hundred later if threat developments dictate. But the expectation is that whatever configuration is selected for the new interceptors will allow them to be placed in the silos that have been constructed at Fort Greely. Those silos are wide enough to accommodate a Minuteman ICBM, so there is plenty of volume within which to make design tradeoffs.
It must be ready for deployment soon. Missile Defense Agency planners want to minimize the time required to switch from existing ground-based interceptors to the next-gen weapons, so pacing of the development program is critical. Some observers think it will take ten years before the first Next Generation Interceptor is delivered, but others involved in thinking through what is doable suggest deliveries could commence around 2026. The timing of when the new interceptors become available will depend on how much funding is allocated and whether any technological show-stoppers arise. Multiple warhead hit-to-kill systems have been under development for two decades and booster technology is well understood, so at least some of the players are optimistic about timelines.
It must be viable for decades to come. The need for a next-gen interceptor is driven by the threat emanating from rogue states whose behavior is considered unpredictable. That means mainly North Korea, but it could also include a future nuclear threat from Iran, and even accidental/unauthorized launches from a major nuclear power like Russia. Recent intelligence suggests that North Korea might grow the number of long-range missiles it has, or “fractionate” them by adding multiple warheads, or use lightweight decoys that mimic the signatures of real warheads. The Missile Defense Agency wants its new interceptor to have capabilities and growth potential adequate to keep up with the rogue-state nuclear threat for many years, no matter how it evolves.
Like interceptors in the existing homeland defense network, the Next Generation Interceptor will rely on target detection and tracking from a diverse assortment of sensors on land, at sea, in the air and in orbit. It may be configured as part of a layered defense in which there is an “underlay” of other weapons capable of intercepting long-range warheads, such as the Navy’s Aegis system. And it will be developed competitively, with two industry teams receiving awards in 2020.
Whether all of this is sufficient to allay the fears of those who think that the existing system cannot be allowed to languish while a next-gen solution is developed remains to be seen. Nuclear attack is the greatest military threat to national security, and the interceptors currently deployed in Alaska are the only weapons in the U.S. arsenal currently capable of intercepting intercontinental-range nuclear warheads. It was inevitable that something better would be needed someday, but the immediate question is what should be done to keep the existing system effective while the Missile Defense Agency pursues more capable alternatives.