In a rare standing vote, US senators voted unanimously on Tuesday to honor the members of the military and intelligence community who killed Osama bin Laden.

It’s a procedure reserved for solemn moments, such as the vote for emergency funding after the 9/11 attacks on the World Trade Center and the Pentagon, which was also unanimous.

Success in the hunt for Mr. bin Laden, which eluded both Presidents Clinton and Bush, gives President Obama new credibility at home and abroad in his leadership on national security. But the fallout from this operation also has reopened three crucial topics for debate, all of which produce anything but unanimity on Capitol Hill: relations with Pakistan, the value of interrogation techniques critics call torture in the hunt for bin Laden, and the ongoing role of US forces in Afghanistan.

"It clearly has a ripple effect in the region, but in ways that may create a whole series of new challenges for Obama,” says Norman Ornstein, resident scholar at the American Enterprise Institute in Washington.

Aid to Pakistan

A top concern for many lawmakers was what Pakistan knew about bin Laden’s fortified complex in a garrison town about 75 miles by road from the Pakistani capital. In floor speeches, congressional hearings and comments off the floor, lawmakers challenged whether the US should continue military and economic assistance to a nation that may not be committed to the defeat of Al Qaeda.

“In a town where the Pakistani military and intelligence services own a large share of the property, Al Qaeda appears to have built a massive complex, ringed by walls as high as 18 feet, protected by barbed wire, as the dedicated hiding place for Osama bin Laden,” said Sen. Carl Levin (D) of Michigan, who chairs the Senate Armed Services Committee during Tuesday’s floor debate on the resolution.

“The American people [who] provided billions of dollars of aid to the Pakistani government deserve to know whether elements of Pakistan’s military and intelligence services or local officials knew of bin Laden’s location over the five years or so he was there – and if they did not know, how that could possibly be the case.”

Rep. Ted Poe (R) of Texas is proposing legislation that would cut off future aid unless the US State Department certifies that Pakistan was not “providing sanctuary” to bin Laden. The Obama administration is requesting $3 billion in foreign aid to Pakistan in fiscal year 2012, along with $2.3 billion in funding to boost that nation’s counterterrorism capacity.

Sen. Frank Lautenberg (D) of New Jersey called for suspending US aid immediately. “Before we send another dime, we need to know whether Pakistan truly stands with us in the fight against terrorism,” he said in a statement on Monday.

But the Obama administration and many Republicans supporting the war effort in Afghanistan are urging caution. “Cooperation with Pakistan helped lead us to bin Laden and the compound in which we was hiding,” said Secretary of State Hillary Clinton in a press briefing on Monday. “Going forward, we are absolutely committed to continuing that cooperation."

The top Republican on the Senate panel that funds US foreign assistance also took a cautionary tone. “Pakistan can’t be trusted, nor can it be abandoned,” said Sen. Lindsey Graham (R) of South Carolina, in comments to reporters on Tuesday.

Did torture provide the breakthrough?

A second line of inquiry concerns just how US officials gained the critical intelligence needed to locate bin Laden – especially, whether “enhanced interrogation techniques,” which critics say amount to torture and which Mr. Obama has banned, contributed to the outcome. The USA Patriot Act, passed after the 9/11 attacks to authorize new law-enforcement and intelligence powers, is set to expire this month.

In a briefing with reporters, Sen. Dianne Feinstein (D) of California, who chairs the Senate intelligence panel, said that she did not believe that torture techniques were a factor in the outcome. “To the best of our knowledge, based on a look, none of it came due to harsh interrogation practices,” she said on Tuesday.

Democrats on the intelligence panel are investigating Bush-era interrogation practices.

On Monday, Rep. Peter King (R) of New York, who chairs the House Homeland Security Committee, told Fox News that “we obtained that information through waterboarding.”

“So for those who say that waterboarding doesn’t work, who say it should be stopped and never used again, we got vital information which directly led us to bin Laden,” he added.

Asked to comment on whether Congress should reopen the issue of interrogation techniques, House majority leader Eric Cantor (R) of Virginia told reporters on Tuesday that “information gained, if valuable in saving American lives, in increasing the security of the United States, is ... a policy that we should have in place.”

The Afghanistan war

But the larger question is how bin Laden’s death will impact ongoing support for the US war effort in Afghanistan, now set to begin to wind down in July. For many Democrats, especially those opposing the wars in Iraq and the buildup in Afghanistan, bin Laden’s death signals an end to the mission first proclaimed by the Bush administration.

“I hope the killing of bin Laden signals the chapter of our military being extended in that part of the world will end, and we will conclude that actionable intelligence and clandestine operations will allow us to deal with our enemies effectively,” says Rep. Marcy Kaptur (D) of Ohio, a member of the Defense Appropriations subcommittee.

Senate Republicans Tuesday aimed to counter that conclusion. Bin Laden’s end “doesn’t change the challenge of radical Islam,” says Sen. John McCain (R) of Arizona, the top Republican on the Armed Services Committee. “We’re going to be in a struggle with radical Islam well into this century.”

Experts offered some support for Senator McCain's view. “A lot of people seemed to suggest there will be a temptation to declare victory and come home,” says Michael O’Hanlon, a senior fellow at the Brookings Institution. “Emotionally, that’s what a lot of people want. But I think there’s a possibility that works in another direction: It gives a boost of confidence in a long slog in a difficult part of the world. The boost to our confidence may count for something."