To answer that question, we must retrace the chain of moral logic link by link. I suspect that a good number of Americans will say the fault lies with the driver of the vehicle, which carried 13-15 people in all. Had the driver stopped when ordered to do so or after warning shots were fired, the victims would be alive today. But some will go further and say the fault also lies with the suicide bomber in a taxi who killed four American soldiers a few days earlier only 20 miles away from the incident. The fault could also be said to lie with the Iraqi guerrillas who dress as civilians and attack U.S. forces. If the American military did not have to worry about suicide bombers and fighters disguised as noncombatants, it is argued, its personnel would be less likely to fear civilian vehicles.

The next step in the chain is Iraq’s President Saddam Hussein (if he’s still alive). Since he is surely sanctioning or authorizing suicide bombers and guerilla tactics, he is ultimately to blame for the deaths at the hands of American soldiers who, it is said, were only exercising their “inherent right of self-defense.” This was the position taken by the U.S. command. “The blood is on the hands of their regime for their willingness to use their population [as human shields],” said Brig. Gen. Vincent Brooks, who conducts the daily news briefing for the U.S. military.

But is it that simple? Not really.

The analysis above leaves unexamined a material fact: the U.S. military was maintaining a checkpoint on an Iraqi road. Whether one approves of the U.S. assault on Iraq or not, it cannot be denied that American forces entered Iraqi territory and did so not in response to an Iraqi attack on the American people or territory. In other words, it invaded Iraq with the intention to remove the government there.

This little detail cannot be ignored. One can argue powerfully that given the U.S. checkpoint and given the real threat from Iraqis who look like civilians, American soldiers must protect themselves. If a civilian-looking vehicle approaches and the driver refuses to stop — even after shouts, warning shots, and a 7.62mm machine-gun round to the vehicle’s radiator — then U.S. personnel have a right to protect themselves and use whatever force necessary to stop the possible threat.

But that seemingly powerful argument has a weak link in its chain of moral logic. Why was the U.S. military maintaining a checkpoint — that is, a roadblock — on Route 9 in the first place? The obvious answer is: that’s what soldiers do in wartime. If troops are taking territory and securing it, they will control traffic with roadblocks. But this just sets the problem back one step earlier. Why is the U.S. military trying to secure territory in Iraq? Or, why is the U.S. government prosecuting an offensive war against Iraq? (It is offensive in the sense that the Iraq government has not attacked or even threatened the United States.)

Assigning responsibility for the deaths of those Iraqi civilians first requires us to determine whether the American soldiers were justified in being in Iraq in the first place. It might be true that if the driver had stopped, those women and children would be alive today. It also might be true that if Iraqis who look like civilians could be assumed harmless, those women and children would be alive today.

But it is also true that if President Bush hadn’t sent soldiers to Iraq those women and children would be alive today. As the pro-war gallery likes to say, tragic accidents and misunderstandings are inevitable in war.

But that is precisely why wars shouldn’t be waged except in self-defense.

Who would argue that this war is in self-defense?

Sheldon Richman is senior fellow at The Future of Freedom Foundation in Fairfax, Va., author of Tethered Citizens: Time to Repeal the Welfare State, and editor of Ideas on Liberty magazine.