John Nagl: Does Military Service Still Matter for the Presidency?

John Nagl, a retired Army officer, is the Minerva professor at the U.S. Naval Academy and a veteran of both wars in Iraq. He is the author of "Learning to Eat Soup With a Knife: Counterinsurgency Lessons From Malaya and Vietnam."

In every presidential election since 1992, the candidate with the less distinguished military résumé has triumphed.

Bill Clinton defeated war heroes George H.W. Bush and Bob Dole; National Guard pilot George W. Bush beat Vietnam veterans Al Gore and John Kerry; and Barack Obama was decisively elected over John McCain, who had displayed extraordinary valor during years of captivity as a Navy pilot in North Vietnam.

In 2012, we won’t have the chance to test this trend: For the first time in modern American history, neither major candidate for the presidency has any military experience.

This is a dramatic change. The crucible of combat not only created these United States but has also given us many of our most successful presidents...