Last week, General James Amos, Commandant of the Marine Corps, issued an order that makes available to women a number of occupational specialties previously open only to men. Although this is supposed to be an experiment and designed merely to inform the Commandant as he ponders a permanent change in some assignment rules, General Amos's order comes as other Services are also changing personnel policies in this way. There are many reasons for this trend, but perhaps the most significant one results from war and the pesky Law of Unintended Consequences.

The entry of women into the American workforce has had an enormous, positive effect on the size of the American economy, growing it manifold a hundred years ago after the huge surge in immigration from Europe, again after World War II, and yet again starting in the 1970s. Although many families have two wage-earners because they can't survive otherwise, the presence of women in professions from which they were virtually excluded has accompanied a revolution in attitudes and demographics. In the past, females in law enforcement, business and even art were iconoclasts. Today, women are the numerical majority among students in higher education and most notably in medical school, where a few decades ago one would have trouble finding more than just a few females.

The trend has been similar in the armed services: the percentage of women is nearly twice what it was fifteen years ago. When I entered the US Army, there was a separate Women's Army Corps whose members performed mostly administrative and logistical jobs. Today, there are no WACs, and the United States is served by female MPs, military engineers and fighter pilots.

However, women are still excluded from serving in the ground combat arms---infantry, armor and artillery, units that can be expected to fight directly against the enemy at close quarters. There have been many reasons advanced for the policy, including the assertion that America is not ready for female casualties, but our combat operations in Southwest Asia have produced an uncomfortable paradox: because of our predilection against women in combat, females have been killed and wounded no less frequently than men.

The proximate cause of this anomaly is ironically the very aversion to having women in combat. If we don't want women to fight the enemy, then we put them in non-combat jobs such as drivers and logistical specialists. But in Iraq and Afghanistan, where toe-to-toe combat has been the exception rather than the rule, most of our casualties have been the result of improvised explosive devices detonated to ambush American convoys that travel down unsecured roads, convoys that are precisely the missions we give many of our female troops.

Sending Americans down roads that are unsecured is lunacy to be sure, contrary to basic tactical principles that the lowest-ranking and least experienced troops learn from their earliest days in the military service. But our leaders do it because we have lacked the will to fill our ranks with sufficient troops to perform these missions properly: clear roads far to the front and flanks---and then hold them until after the convoys pass safely. Doing otherwise demonstrates either ignorance or callous disregard, and as citizens who are comfortable to let others shoulder the burden, we are all complicit.

But when we structure policies to keep women away from the front lines in environments where there are no front lines, we should not be surprised when the policies do not keep female troops from harm. It's too late to argue that women should not be in combat. They are already there.