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GMD interceptor emplacement
While the midcourse sergment of a national missile defense system is taking shape, should the current plans for similar boost-phase interceptors be scrapped in favor of a space-based system? (credit: Boeing)

Save missile defense: cancel KEI

There is a story, probably apocryphal, concerning a British army general who was ordered in 1991 to cut his forces’ budget. He gathered his staff together and gave them their orders: “Gentlemen, we have run out of money. Now we must learn to think!” The Missile Defense Agency (MDA), under Air Force General Trey Obering, has, according to reports, been ordered to cut five billion dollars out of its six-year plan. It now faces a similar educational requirement.

Press reports indicate they have three choices: cut a little here and a little there, hoping to save all of their ongoing programs; cut the Airborne Laser (ABL); or cut the Kinetic Energy Interceptor (KEI). Sitting outside MDA, the answer is obvious, to wit, kill KEI. It is a program that never should have been started in the first place.

KEI is supposed to be a boost-phase interceptor (BPI). That is, it is designed to kill an enemy ballistic missile in the very early stages of its flight. This is, of course, the best possible moment to intercept an enemy missile. It is still struggling with gravity as it fights its way though the heavy soup of the Earth’s lower atmosphere, and it is putting out joule upon joule of heat, making it an ideal target for infrared guided weapons.

Sitting outside MDA, the answer is obvious, to wit, kill KEI. It is a program that never should have been started in the first place.

KEI is planned to be a BPI system that will be based on land and, later, in ships and even on aircraft. The first version to be deployed will be fitted onto a transportable trailer that can fit inside a C-130 aircraft; this trailer can be trucked up close to the borders of an enemy nation that is preparing to launch long-range missiles at US or allied targets. It would be difficult to imagine a worse solution to the BPI problem.

To begin with, the KEI will have to have an exceptionally powerful booster rocket in order to catch up with the missile it is supposed to hit. After all, by the nature of the mission, it will be trying to catch up with a target that has already been launched. If the enemy missile maneuvers or changes velocity, the KEI booster will have to adjust, thus bleeding off its own power. Also, being close to an enemy’s border, the launcher and its associated systems will be vulnerable to short-range enemy weapons. The launch of an ICBM or IRBM could be preceded by a barrage of shorter-range rockets of the Frog or Al Samoud type, equipped with cluster bombs.

Politically, the idea of land-basing BMD weapons on the soil of our allies makes no sense. For their own domestic reasons, they will want to ensure that no weapons are fired from their soil without their permission. In a real emergency, getting permission might involve panicked political leaders or communications failures that might leave the enemy missile flying freely towards the US mainland. Any arrangements for consultation, or even a dual-key arrangement, would reduce intercept time by precious seconds. For a BPI weapon, this makes all the difference.

A country larger than North Korea—say, Iran—would not find it difficult to base its long-range missiles far away from its borders, creating a difficult or impossible intercept problem for the KEI. The geometry of such a mission, if the target missile is launched from more than 650 kilometers from the KEI, would make the intercept more of a midcourse encounter than a boost-phase one.

Sea basing solves most of these political problems, but not the physical ones. A ship that got close enough to an enemy coast to carry out the intercept would also be close enough to be attacked. An Aegis radar-equipped ship, under attack by multiple cruise missiles, would scarcely have the ability to use its radar to track the near-simultaneous launch of an ICBM. Also, the modifications of the Navy’s VLS launch system required to accommodate the large-diameter KEI booster will radically drive up the cost of a sea-based KEI.

The US Navy already has the SM-3 missile for Aegis ships in late-stage development. This should give them some limited capability before the end of 2005. Sadly, there does not seem to be much funding available to improve the SM-3 missile to give it the ability to perform the same sea-based BPI job at far less cost than the KEI.

The MDA is quietly putting the Ground-based Midcourse Defense (GMD) national missile defense system into place. It has not yet been declared operational, and probably will not be, until after more successful testing has been carried out. Last month’s GMD failure was traced to a small, but critical, software glitch that can be fixed, but it shows that more testing in needed. The GMD is a midcourse defense system and it needs to be complemented by something that can hit incoming warheads in their terminal phase, as well as by BPI weapons. There has been talk of modifying the Theater High Altitude Area Defense (THAAD) weapons for this purpose, and also the possibility of giving some terminal defense capability to a new version of the SM-3.

What is needed is to renew work on space-based boost-phase interceptors.

The ABL is not a perfect BPI system either. It may not be as exposed to enemy attack as a land- or sea-based KEI platform, but it is scarcely invulnerable. For certain regional missions, the early version will probably be highly effective. With the ability to hit Scud-type or larger missiles in the ascent phase at ranges of about 650 kilometers, the ABL will be a highly effective part of an airborne warfighting network. When combined with AWACS and J-Stars radar aircraft, or the future E-10, as well as being able to use data from space-based assets such the DSP and SBIRS-High infrared sensing satellites, and with data from fighter radars, the ABL will be a critical part of future US air supremacy task forces.

The ABL will probably have uses far beyond simply targeting theater ballistic missiles including, but not limited to, suppression of enemy air defenses. As a potential multi-purpose weapon, it may become a low-density high-demand asset. Canceling it now, when the program managers have overcome so many obstacles, and after so much effort, would be extremely foolish. Before the end of this decade, the ABL will, if it is not canceled, will be an essential part of any USAF air dominance campaign.

What is needed is to renew work on space-based boost-phase interceptors. The political obstacles are formidable indeed, but the case for Brilliant Pebbles or similar systems is as valid now as it was when the system was canceled by the late Les Aspin with the notorious quip, “I’m going to take the stars out of Star Wars.” Orbiting BPI weapons will not only give the US the capability to shoot down long-range missiles aimed at us but, and more importantly, it could allow the US to smother regional ballistic missile exchanges. Pick your own favorite nuclear missile nightmare scenario, and imagine how it would be changed if both sides found that their rockets were being knocked out of the sky. In a world full of nuclear proliferation, space-based BPI would be the ultimate diplomatic tool.