From Bill Gertz, Inside the Ring:  The Obama administration is set to offer more concessions to the Russians on missile defense, the latest one a proposal to share secret technical data on the U.S. military’s most effective anti-missile interceptor.

Word of the proposed offer is causing concern among missile defense advocates on Capitol Hill who have questioned the administration’s past secret dealings with the Russians, led mainly by Ellen Tauscher, undersecretary of state for international security and arms control.

According to U.S. officials, Mrs. Tauscher discussed the proposal in recent talks with the Russians couched as an offer of technical data on the Navy’s SM-3 missile burnout velocity, called VBO. The idea behind the offer is to assuage Russian fears that U.S. missile defenses in Europe will target Moscow’s missiles.

The velocity of a rocket when it runs out of fuel is a key technical feature that, if known by an adversary, could be used to counter it.

It is suspected that U.S. negotiators believe that providing the burnout data would help convince Moscow that current SM-3s are not fast enough to hit Russia’s long-range missiles.

Critics, however, say engaging in discussion of missile speed limits is the first step by Russia in seeking limits on interceptor speeds, as was discussed and rejected during earlier U.S.-Russia talks in the 1990s. . . .

Rep. Michael R. Turner, Ohio Republican and chairman of the House Armed Services strategic forces subcommittee, said in a speech Wednesday that he is very concerned about sensitive missile defense data being compromised by Mrs. Tauscher’s negotiating effort.

Mr. Turner said Republicans will "oppose any effort by the administration to provide to Russia information on the burnout velocity, also known as VBO, of SM-3 missile interceptors."

"The House Armed Services Committee will vigorously resist such compromise of U.S. missile defense systems capabilities," Mr. Turner said. . . .

[T]he White House in May rejected a draft agreement with the Russians that was drawn up by Mrs. Tauscher over concerns that the agreement would have legally binding limits on defenses.   (photo: U.S. Department of State)

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