“We don’t have boots on ground providing intelligence and we don’t have confidence in information that the Iraqi government provides, because they’ve [been] so heavy-handed in the use of force against Sunni villages,” said Rep. Adam Schiff, D-Calif., a senior member of the House Intelligence Committee.

In other words, the American intelligence community is only now scrambling to draw up a potential target list in Iraq, and possibly Syria—even though the threat of ISIS has been visibly growing for years. And while the analysts are trying to figure out who they should zero in on, Obama administration lawyers are wrestling with what legal authorities the president might have to carry out an attack.

While ISIS is taking over cities like Mosul and Tikrit—acquiring the equipment of a modern army in the process—a strike on ISIS wouldn’t be as simple as, say, attacking one of Saddam’s tank columns during the last Iraq war. It requires a different kind of intelligence. The prime objective is to detain or kill individuals who are indispensable to the networks used by terrorists to conduct their attacks. This model means that the drone strike is the last piece of a long process to identify, locate and verify where an individual target resides. And while that work has been enhanced by high-tech gadgets that can intercept cellphone traffic, it still requires the basic tradecraft of human spying.