In the old days, before we went to war, Congress had to declare one. In the old days you couldn’t kill an enemy combatant unless we were in a declared war. In the old days, an enemy combatant was someone wearing a uniform on a field of battle.

How times have changed. As I wrote last week, President Obama, sitting in the White House, can authorize the killing of people who are not in uniform, are not armed and are nowhere near a field of battle. The people killed may never have harmed an American. They may have no intent to ever harm us. They are targeted because they have a connection to other people we don’t like. Or maybe they don’t. According to Jo Becker and Scott Shane at The New York Times, the White House “counts all military-age males in a strike zone as combatants.” So if a young man is standing next to a target, the young man is viewed as a target as well.

Conducting remote control warfare with the use of drones, far away from any combat zone is a practice that didn’t start under Barack Obama. But he has carried it out to an extent that goes far beyond anything ever seen before. In the president’s first five years in office, the C.I.A. made 330 drone strikes in Pakistan alone, compared with 51 strikes in four years of George W. Bush’s presidency.

Assuming the target of a drone strike deserved to die, how many untargeted people have been killed just because they happened to be somewhere near him? The C.I.A., in classified submissions to Congress, claims civilian death rates are “typically in the single digits.” Independent estimates differ with that. Pratap Chatterjee, writing in The New York Times reports that:

In 646 probable drone strikes in Pakistan, Somalia and Yemen recorded by the Bureau of Investigative Journalism, as many as 1,128 civilians, including 225 children, were killed—22 percent of deaths. The New America Foundation’s estimates are lower, but suggest a civilian death rate of about 10 percent.

So how does this affect the guys sitting back in places like the Nevada desert, well out of harm’s way—the guys who “pull the trigger” so to speak? Chatterjee writes:

The Air Force is providing psychological support for drone personnel, but this interim solution seems unlikely to be adequate.

“We can say we see children and we think you shouldn’t do it. But it isn’t up to us,” one former analyst, who asked to remain anonymous, told me. “We are completely outranked, and at the very bottom of the food chain.”

One particularly troubling practice is the “double tap” drone strike—the practice of deliberately attacking civilians rescuing the wounded, or the wounded themselves. Dylan Matthews, writing at Vox, reports:

In 2012 the Bureau of Investigative Journalism reported that the Obama administration had killed at least 50 civilians in the course of double tap strikes up to that point. That doesn’t include the more than 20 deaths at drone strikes that hit funerals and mourners.

Here is another troubling fact: We sometimes target people with drones whose identities we don’t even know:

A signature strike, the Washington Post’s Greg Miller explains, “hit targets based solely on intelligence indicating patterns of suspicious behavior, such as imagery showing militants gathering at known al-Qaeda compounds or unloading explosives,” rather than upon intelligence about a specific person’s involvement in al-Qaeda, and intelligence about their location.

We have apparently killed at least four US citizens in drone strikes.

One thing to keep in mind: Drone technology will quickly make its way around the world. How would we react if Russia or China used a drone to kill someone on US soil? I’m sure we wouldn’t like it. But what kind of precedent have we set—for every other country to follow?