Pakistan's military and its main intelligence service, the Inter-Services Intelligence Directorate (ISI), saw things differently. After the ISI discovered that Afridi had visited Bin Laden's house just before the raid, its agents arrested him as he was driving home in Peshawar on May 23, and as they say in Pakistan, "he was disappeared." Afridi was taken to a secret prison, leaving unanswered the question of what exactly happened that day in Abbottabad.

When I arrived in the border city of Peshawar this summer to learn more about Afridi, the doctor's grim fate had come to symbolize the ongoing animosity between America and its ostensible ally. Peshawar—dusty, crowded, its avenues lined with mirrored-glass shopping comples and crumbling old office buildings—sits on the outskirts of Pakistan's tribal areas, where the CIA is waging a drone-warfare campaign against Al Qaeda and the Taliban. Pakistan's military has long grown fed up with the drone attacks and various other "unilateral missions," in which the CIA operates without its knowledge and consent. Military officials believe the CIA is bribing a vast network of local informants inside the country, not only to hunt Al Qaeda and the Taliban but also to spy on Pakistan's nuclear weapons, which some U.S. officials worry could one day fall into the wrong hands. Afridi—and the mission to kill Bin Laden—was a realization of the ISI's greatest fears.

The Americans, meanwhile, believe Pakistan's military maintains links to militant groups like the Haqqani network—a powerful insurgent group fighting the United States and NATO in Afghanistan—in order to further its influence in the region. The mistrust had taken hold outside the gates of the U.S. consulate, where I saw Pakistani police standing guard, dressed in black-and-khaki uniforms and carrying assault rifles. According to journalists and officials I spoke to, anyone leaving the compound was likely to be tailed by plainclothes Pakistani intelligence agents, who suspected the consulate of being a hotbed of spies; what else would they be doing in a city like Peshawar? "The consulate has a lot of suspicious types with bulging biceps, wearing Oakleys," one ISI official told me. "It's just like Berlin at the height of the Cold War. Every agency worth their name has people here."

Operation: Free Afridi *

Senator Rand Paul of Kentucky discusses the government's efforts (or lack thereof) to secure the release of Dr. Shakil Afridi.—Christopher Swetala

Should the U.S. government try to secure the doctor's freedom?

Of course. We got Bin Laden with some help from this gentleman.

What can you do?

Our only leverage is withholding foreign aid. The current administration, however, has done the opposite—they've actually given Pakistan more money. We released a billion dollars extra over the summer. You shouldn't have to bribe your allies. If you do, you ought to get freedom for people who helped us get Bin Laden.

But didn't Congress propose withholding $33 million from Pakistan—a million for every year of Afridi's sentence?

That was a pittance. It didn't deter them at all. When we met with their ambassador afterward to press for his release, she just laughed at it. She basically said he's a bad man and we don't understand what we're talking about.

Is the State Department working to negotiate his release?

We met with Marc Grossman [special representative for Afghanistan and Pakistan] before we met with the ambassador. We let him know what we were doing. If there were some sort of secret negotiations, we didn't want to get in the way. But we were never given any information that anything was being done. I think they've given up on him.