Why has the US not demanded AQ Khan from Pakistan? It's a question Laura Rozen has asked in the past, and with new information via the CIA pointing to Khan possibliy supplying Iran with both centrifuge and warhead designs I dare bring it up again:

A new report from the Central Intelligence Agency says the arms trafficking network led by the Pakistani scientist A. Q. Khan provided Iran's nuclear program with "significant assistance," including the designs for "advanced and efficient" weapons components.

The unclassified version of the report, posted Tuesday on the agency's Web site, www.cia.gov, does not say explicitly whether Mr. Khan's network sold Iran complete plans for building a warhead, as the network is known to have done for Libya and perhaps North Korea. But it suggests that American intelligence agencies now believe that the bomb-making designs provided by the network to Iran in the 1990's were more significant than the United States government has previously disclosed.

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Until now, in discussing Iran's nuclear program, American officials have referred publicly only to the Khan network's role in supplying designs for older Pakistani centrifuges used to enrich uranium. But American officials have also suspected that the Khan network provided Iran with a warhead design as well.

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Mr. Khan remains in Pakistan, where he was pardoned last year by President Pervez Musharraf. Libya turned over the design to the United States early this year, and it is now being examined at the Department of Energy, the custodian of the American nuclear arsenal.

Wouldn't apprehending Khan be a crucial step in making conjecture concrete evidence against Iran? Simply go directly to the source for the info. So, why is the US not attempting to do just that?

Perhaps the administration is fearful of Musharraf withdrawing his troops from the Pakistani/Afghani border region, those who continue to hunt down suspected al Qaeda members. Certainly the US is currently too overstretched to replace Pakistani soldiers in such an effort. Although, Musharraf has been firmly in the administration's pocket for years now. If anything, he needs US support in order to recieve economic incentives to further consolidate his power and protect him from his own radicals. Forcing Musharraf to give up Khan would seem to be an easy task for the administration. Even if they did lose Pakistani favor, it would be a small price to pay for the information Khan holds — when was the last time Pakistani troops actually captured or killed a signifcant al Qaeda member, anyway?