Ever since the Boston Marathon bombings Monday, something has been bothering me. I've tried to put it out of my mind, but I can't. So, perhaps unwisely, I'm going to write about it.

We Americans are justifiably outraged at the attacks in Boston, which killed three innocent people and injured many more. But over the past 12 years our own nation has killed and maimed thousands of innocent people while carrying out military operations in Iraq, Afghanistan and Pakistan. Estimates of war casualties are notoriously unreliable and should always be viewed with skepticism. But according to the reputable group Iraq Body Count, between 2003 and 2011 U.S.-led coalition forces in Iraq killed 14,906 civilians, including at least 1,201 children.

Such killings continue. On April 8, The New York Times reported that an American airstrike in Afghanistan killed at least 10 children and wounded at least five women. The incident was not even major news; it ran not on the front page of the Times but on page eight, because incidents like these are common. How can we condemn the killings in Boston but excuse the killing of civilians by our soldiers in war zones?

One obvious response is that, unlike the Boston bombers, the U.S. pilots did not want to harm civilians. Their target was a Taliban commander. The U.S. military prefers not to kill civilians and often apologizes when it does. Intention matters, morally and legally; intention is what distinguishes murder from manslaughter. But if you keep doing something over and over again, at some point apologizing and saying you didn't mean it becomes meaningless. Doesn't it?

The U.S. clearly has a double standard for judging killing of civilians, but it's not just that we value American lives more than non-American lives. Let's say the second Boston bomber, who is reportedly from Chechnya, holes up in a house with civilians, including some of his family members. Will law-enforcement agents call in an airstrike to blow up the Bomber along with everyone else in the house? Of course not. The agents will do all they can to protect the lives of the civilians in the building—and even the life of the Bomber!

Police will try to capture alive the Bomber so he can be tried. If he cannot afford a lawyer, the U.S. will give him one. Even mass murderers receive all the benefits of our legal system, which shows what a great civilization, in the best sense of the word, we are. (For the purposes of this essay, I'm going to ignore our unjust detainment of prisoners in Guantanamo Bay as an aberration.)

But consider this irony: We treat child killers here in the U.S. with more care than we treat children in Afghanistan and other war zones. We excuse the killing of civilians by U.S. troops by saying that in war bad things happen--as if war is like a plague or natural disaster, for which we are not responsible. Killing innocent people is inexcusable, whether they live in Boston or in Afghanistan. Terrorists and criminals and deranged maniacs kill civilians. A civilized nation doesn't. Or shouldn't. Ever.

Postscript: Some commenters below raise reasonable objections to my criticism of U.S. military actions, which often kill civilians. I am not a total pacifist, and I do not advocate unilateral U.S. disarmament. I accept that in some cases violence is morally justified to prevent greater violence. But the U.S. is now employing military violence and the threat thereof in ways that are immoral. I present ideas about the justified use of force in past posts on just-war theory, on U.S. drone strikes (see here, here and here) and in my book The End of War. My basic argument is that when contemplating the use of lethal force, we should consider whether our actions will perpetuate war and militarism or help us transcend them. We have a moral obligation to seek the end of war, once and for all.

Post-postscript: Susan Quinlan, an Oakland-based peace activist, recently sent me an email that raises a serious objection to an assumption I make above. Our exchange follows:

"Dear John, I agree that the hypocrisy of lamenting the deaths in Boston while ignoring the far greater destruction inflicted by the U.S. in Iraq, Afghanistan, etc. deserves our attention. Having recently read a very thought provoking article that takes a different approach to the same issue, I feel inspired to challenge you on an area where I believe you could strengthen your argument. Your claim that U.S. law enforcement does all it can to protect innocent (and innocent until proven guilty) civilians struck me as untrue. 'Will law-enforcement agents call in an airstrike to blow up the Bomber along with everyone else in the house? Of course not. The agents will do all they can to protect the lives of the civilians in the building—and even the life of the Bomber!' I want to remind you of the bombing of the MOVE household (and surrounding neighborhood) in Philadelphia in 1985, or the hundreds (thousands?) of people—usually young people of color— who have been killed by police with relative impunity. Aiyana Jones, Oscar Grant, Allan Blueford, Kimani Gray, to name a few. [See http://en.wikipedia.org/wiki/List_of_killings_by_law_enforcement_officers_in_the_United_States]. I urge you to read Mia McKenzie's article and consider how your article might be edited to acknowledge the experiences of people of color in this country. [See http://blackgirldangerous.org/new-blog/2013/4/22/hey-white-liberals.]

Susan Quinlan, BAY-Peace: Better Alternatives for Youth

Horgan: "Susan, you're right. I'm talking about an ideal of U.S. law enforcement that is too often not met, especially when it comes to people of color. But most Americans were horrified by the MOVE bombing, which was a rare event, whereas few care about U.S. military bombing of civilians overseas, which is routine."

Quinlan: "Yes the MOVE bombing was uniquely horrifying, but police violence is an every day part of life in this country—at least in communities of color. I'll bet most high school students in any inner city today could name at least one unarmed person killed by the police. It's hard to write for a national audience because our nation is so divided in this type of experience. However, even though your point was to shed light on the international abuse of civilians (something we all need to be reminded of!), McKenzie makes a clear case for the damage that is done when those of us who are less vulnerable to domestic abuse ignore the issue."

Photo of Afghan children allegedly killed in U.S. air strike: Associated Press/Naimatullah Karyab.