I don’t know if we can prove beyond the shadow of a doubt Pakistani complicity in the whereabouts of Osama bin Laden or the attack on the compound, though I have my suspicions. But it will be interesting to see how that affects the Afghanistan war. Pakistan wants to be a player in any peace deal involving Hamid Karzai and the Afghan Taliban. I don’t know if whatever happened on bin Laden facilitates that. What I do know is that his death has increased calls for drawdown from US progressives.

The leaders of a House liberal caucus pressed President Obama on Wednesday to approve a “significant drawdown” of U.S. troops from Afghanistan this summer now that Osama bin Laden’s been killed.

Six top members of the Congressional Progressive Caucus, including its co-chairmen, Reps. Raul Grijalva (D-Ariz.) and Keith Ellison (D-Minn.), urged the president to use the successful assault against bin Laden in Pakistan as a pretext for hefty cuts to the U.S. troop presence in Afghanistan.

“You acted decisively in your efforts to capture the mastermind behind those tragic events and we commend your calls for national and global solidarity as we acknowledge the world is safer for his absence,” the lawmakers wrote. “It is our hope that you can similarly unifY the nation by bringing our troops home and ending America’s longest war in history- a position supported by an overwhelming majority of the American people.”

You could envision some scenario where a regional deal gets inked with the pressure of Al Qaeda out of the picture, opening the door for withdrawal. I don’t think that will happen so quickly. As Jonathan Landay speculates, this could change the strategy – a de-emphasizing of Al Qaeda as a casus belli for the war and an increase in emphasis on the home-grown insurgency – but not necessarily a change in force size. But one lawmaker is being pretty bold in saying that the costs are no longer justified – Republican Sen. Richard Lugar.

“Clearly it would not be in our national security interest to have the Taliban take over the government or have Afghanistan reestablished as a terrorist safe haven,” Lugar said in a Tuesday statement. “But the President has not offered a vision of what success in Afghanistan would entail or how progress toward success would be measured.”

Lugar added that, with only 100 Al Qaeda remaining in Afghanistan, the country “does not carry a strategic value that justifies 100,000 American troops and a $100 billion per year cost, especially given current fiscal restraints.” Plus, the very fact of the raid inside Pakistan shows that no safe haven is truly safe, nor do we have no tools we’re willing to use to deal with the prospect of a safe haven, even if we aren’t holding the country in question under occupation. We obviously have no problem responding to terrorists at any time and any place.

We’ll have to see how this plays out over a number of months. But I would not be surprised to see a gradual shift in priorities away from Afghanistan. With public attention at a high level, now would be a good time to start that.