In floating an idea for a missile-defense kill vehicle that could work on two of the U.S. military's signature programs, Republicans in Congress might also mend some long-running political divisions between them and their Democratic counterparts.

The Obama administration and Democrats in Congress have emphasized the need to address theater missile-defense threats. It has reduced spending on the national missile-defense system known as Boeing's Ground-based Midcourse Defense System (GMD), in favor of investing in a phased adaptive approach (PAA) positioned in Europe to protect the eastern U.S. from an Iranian missile launch.

Pointing to the recent failed launch test by North Korea, Sen. Jon Kyl (R-Ariz.) and other Republican lawmakers contend that the current balance has leaned too far toward regional missile defense—with the Missile Defense Agency (MDA) planning to spend $20 billion in fiscal 2012-16 on such programs, compared with $4 billion on the GMD.

But there is finally a new wrinkle in the long-running congressional debate over missile-defense investments. Rather than continuing to call on the administration to explain how it will address a potential gap in the U.S.'s defense against long-range missiles before the final stage of the PAA is ready in 2020, Republicans are proposing new business for Congress that might make political sense as well.

Boeing, Lockheed Martin and Raytheon are all in the process of developing plans for the final phase of the administration's PAA, the SM-3 Block IIB.

Kyl suggests that Congress tell the MDA to ask for development of a kill vehicle for the PAA final phase that can also work on the GMD.

“Because the [SM-3 Block] IIB kill vehicle must be made smaller than the current [Ground-based Interceptor (GBI)] kill vehicle—to fit into the smaller SM-3 missile—there is an opportunity to put multiple kill vehicles on the GBI, thus significantly improving the GMD system,” Kyl said in a speech at the Capitol Hill Club April 17. “I intend to work with the armed services committee to see to it that MDA explores the feasibility of this approach—which would mean a real, serious upgrade to the GBI.”

Along with a technological solution that could aid the Obama administration's plans for a PAA to missile defense in Europe, it would also answer Republican calls for a “hedge” against threats to the U.S. by giving a shot in the arm to GMD. But the idea is reminiscent of the Multiple Kill Vehicle terminated in 2009 by then-Defense Secretary Robert Gates.

Kyl appears to have some support in the House—the strategic forces subcommittee of the House Armed Services Committee is scheduled to mark up its version of the defense bill April 26. The subcommittee chairman, Rep. Michael Turner (R-Ohio), “believes as well that we need to continue to modernize our missile-defense capabilities,” his spokesman Tom Crosson says in an e-mail. But Crosson would not comment on the specifics of Kyl's proposal.

A congressional aide explains that Kyl's approach makes sense for a couple of reasons. A warhead for the SM-3 Block IIB would be far smaller than GBI's current exo-atmospheric kill vehicle (EKV), which is having difficulties in testing. The smaller size could allow room then, for two or more kill vehicles, doubling the firepower, he says. Not only that, but the current GBI kill vehicle was developed more than a decade ago, he says; a new one would help ensure that parts for the GBI's system do not become obsolete.

The aide suggests that this could be a political compromise to the Obama administration's support for the PAA and the Republicans' support for GMD.

“Instead of [exo-atmospheric kill vehicle], let's call it [adaptable kill vehicle],” the aide says.

And Sen. Richard Shelby (R-Ala.) alluded to the idea in an exchange with MDA Director Lt. Gen. Patrick O'Reilly on April 18. O'Reilly testified that a redesign of GMD's exo-atmospheric kill vehicle has slowed testing on the overall program. “It's my understanding that the EKV was never meant to be the permanent kill vehicle for GMD, and the current system is heavier, less capable and less reliable than I think it can or should be,” Shelby said, asking whether the U.S. is locked into this version.

O'Reilly endorsed the current system's ability, saying it could be made “very viable, reliable.” He added that the SM-3 Block IIB would give the military the chance to apply the latest technologies to smaller, more capable kill vehicles as well as the possibility of more than a single interceptor.