"This war, like all wars, must end"

It is in this context that the United States has taken lethal, targeted action against al Qaeda and its associated forces, including with remotely piloted aircraft commonly referred to as drones. As was true in previous armed conflicts, this new technology raises profound questions – about who is targeted, and why; about civilian casualties, and the risk of creating new enemies; about the legality of such strikes under U.S. and international law; about accountability and morality.

Let me address these questions ... Simply put, these strikes have saved lives. ... Moreover, America’s actions are legal. ... Under domestic law, and international law, the United States is at war with al Qaeda, the Taliban, and their associated forces. ... So this is a just war – a war waged proportionally, in last resort, and in self-defense." 

The Atlantic Wire: Read Obama's Big Speech on Drones and a New 'Targeted' War, May 23, 2013 

While Obama would not declare an end to the war on terrorism, Obama offered to work with Congress to constrain some of his own authorities for waging it, reflecting what he and aides described as a discomfort with permanent executive war powers. He said he was “open” to working with Congress to establish some additional mechanism to oversee the proper targeting of terrorists, such as a court modeled on the secretive one that oversees the surveillance of suspected foreign agents. He also expressed a preference to constrain “and ultimately repeal” the broad latitude of warmaking powers granted in the 2001 Authorization to Use Military Force (AUMF), the legislative wellspring of the war. “This is the moment to ask ourselves hard questions,” Obama said.

Wired: Obama Swears Drone Surge Is Done, May 23, 2013