In a sweeping national security speech on Thursday, President Obama laid out a new vision for U.S. foreign policy that sought to limit the use of aggressive counterterrorism tactics that have become a hallmark of his administration. And in so doing, Obama sketched a future in which the U.S. would one day bring a close to the defining national security struggle of the post-9/11 era: The war on terror.

Specifically, Obama addressed the U.S.'s heavy reliance on drone warfare in his hour-long speech at the National Defense University in Washington, D.C. While Obama strongly defended the program — "Simply put, these strikes have saved lives" — he also for the first time set down explicit limits on the use of drones.

Most importantly, he said the main legal justification for the U.S.'s various counterterrorism policies — the 2001 Authorization for Use of Military Force Act, passed in the immediate aftermath of 9/11 — would "ultimately" be repealed. The statement has assuaged concerns, at least in some quarters, that the U.S. would use the legislation to conduct an endless war against perceived enemies around the world.

Here's Andrew Sullivan at The Dish:

Our goal must not be an endlessly ratcheting of terrorist and counter-terrorist violence that creates more enemies than friends. Our goal must be normalcy and freedom, even as we continue strong counter-terrorism strategies outside of the context for warfare. [The Dish]

So what specific limits did Obama propose on drone warfare? And do they go far enough?

He touched on his administration's controversial decision to target an American citizen with a missile strike, a day after the administration acknowledged killing Anwar Al-Awlaki, a U.S.-born cleric who was a leader of Al Qaeda's branch in Yemen. "For the record," Obama said, "I do not believe it would be constitutional for the government to target and kill any U.S. citizen — with a drone, or a shotgun — without due process."

Significantly, however, he did not define what, exactly, constitutes due process.

Still, Obama was adamant about the legality of killing Awlaki, who he said was active in several terrorist plots:

But when a U.S. citizen goes abroad to wage war against America — and is actively plotting to kill U.S. citizens; and when neither the United States, nor our partners are in a position to capture him before he carries out a plot — his citizenship should no more serve as a shield than a sniper shooting down on an innocent crowd should be protected from a swat team. [PDF]

The justification appears to fall in line with a new classified policy guidance that Obama signed on Wednesday. According to the New York Times, attacks would be authorized only against targets who are "a continuing, imminent threat to Americans," as opposed to those who are simply members of Al Qaeda or associated groups. The guidance would also curb attacks in places that are not overt war zones, like Yemen, where Awlaki was killed.

In addition, Obama in his speech said, "Nor should any President deploy armed drones over U.S. soil."

In another revelation, Obama defended the amount of oversight over the drone program, claiming that "not only did Congress authorize the use of force, it is briefed on every strike that America takes" — including the attack on Awlaki.

It remains unclear whether the government's drone program will become anymore transparent. Here's Mark Mazetti at The New York Times:

[O]ne of the big outstanding questions is just how transparent the Obama administration will be about drone strikes in the future. Will administration officials begin to publicly confirm strikes after they happen?

There was no mention of this in the speech, and it is telling that the president did not mention the C.I.A. at all. It seems quite certain that past operations in Pakistan, Yemen and elsewhere are not going to be declassified anytime soon. [New York Times]

Obama also said that he would consider two plans to strengthen oversight of the drone program, noting that each one has "virtues in theory, but poses difficulties in practice."

One is to establish a special court to review each drone strike, which "has the benefit of bringing a third branch of government into the process, but raises serious constitutional issues about presidential and judicial authority." The government, going back to the Bush administration, has regularly argued that the executive branch should have the final say on issues of national security.

The other is to create an independent oversight board in the executive branch, which Obama said could introduce an unwanted "layer of bureaucracy into national security decision-making."

While some liberals were happy with the speech, others said the new guidelines would still allow the government to conduct its counterterrorism program without any meaningful checks and balances. And Obama's rhetorical concern about civil liberties has not always matched his actual policies. Here's The Guardian's Glenn Greenwald:

As for conservatives? Sen. Saxby Chambliss (R-Ga.) quickly released a statement decrying the limits Obama had placed on U.S. power: "The president’s speech today will be viewed by terrorists as a victory."

For Jennifer Rubin at The Washington Post, Obama got one thing right: "The speech was not all bad. He defended the use of drones overseas to kill terrorists."