In 2010 alone, Obama oversaw the killing of 500 suspected militants in Pakistan, according to the Counterterrorism Strategy Initiative. The kill-to-capture ratio has prompted questions about the strategic and moral foundation of Obama’s approach.

A debate has emerged on this tactic: has Obama given up capturing terror suspects in favor of killing them?

Senator Saxby Chambliss, the ranking Republican on the Intelligence Committee, believes that is exactly what’s happening.

“Their policy is to take out high-value targets, versus capturing high-value targets,” he told the New York Times in May, when it broke the news of Obama’s “kill list.”

It’s a serious allegation. Human rights law requires that the military capture when possible. Killing for expediency is generally prohibited, and the U.N. opened an investigation into Obama’s policy on this score. White House officials, however, emphatically deny such charges.

“It’s always our preference to capture,” says Vietor, who noted past policy statements echoing the point by John Brennan, Obama’s top adviser on counterterrorism.

“Whenever it is possible to capture a suspected terrorist, it is the unqualified preference of the administration to take custody of that individual,” Brennan has said, “so we can obtain information that is vital [to national security].”

The formal denials of a policy that favors killing over imprisonment don’t convince everyone. Author Daniel Klaidman, who just finished a book probing Obama’s counterterrorism policies, argues that members of Congress from both parties, particularly in their opposition to closing Gitmo,  ”did not give president the flexibility that he needed” on counterterrorism policies.

As a result, Obama was left with a  ”legal morass” that created “unspoken but real incentives” to avoid capturing suspects and “incentives for more killing,” Klaidman argues.

“I didn’t uncover anybody saying that in a meeting,” Klaidman added, referring to the reporting for his book, which is called “Kill or Capture: The War on Terror and the Soul of the Obama Presidency.” “But I don’t think people say those things in meetings.”

Some human rights critics of the administration’s foreign policy, however, dispute the premise that congressional roadblocks were key to shaping Obama’s path.

“Congress has done nothing to make it more difficult to capture or detain suspects,” says Chris Anders, senior legislative counsel for the ACLU, which is suing the CIA and Defense Department over targeted killing policies.

Anders does criticize Congress for backing Guantanamo and indefinite detention “without charge or trial,” but he is convinced that the buck stops with the president.

“The decision to use targeted killing lists is squarely one made by the White House, with Congress sidelining itself,” he  says.

Finally, there is one more complicating factor that has very little to do with politicians: the evolution of the battlefield itself.

National security experts say that while the rules crafted in Washington do matter, in the current phase of this war, more threats emanate from places where capturing people on the ground is not feasible.

Korb believes there should be a real national debate over drone attacks, which he stresses are “acts of war.” But he also believes that drones may offer the most limited military option.

“I don’t want to send large land armies into Yemen to capture al-Aulaqi,” he said, referring to the first American citizen killed under the targeted killing program.

Neither did officials in Washington. For the foreseeable future, that likely means the political branches of government will keep shooting first, and asking questions later.

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