The Concord Monitor provides a brief look at veterans in U.S. politics throughout the years.  Some facts they've compiled:

--Since the draft ended in 1973, U.S. citizens serving in the military fell to 1% of the population.
--31 of the 42 presidents were veterans.
--The 2008 election could mark the first time since World War II that a veteran isn't on the final ballot (if McCain doesn't make it).
--In the generation from 1870 to World War I, it really did matter if a campaigning candidate had fought in the Civil War.

The article goes on to look at whether military experience really does impact how a political leader conducts a war.  There was James Madison (civilian) who was in charge during the War of 1812 when the White House burned:

"It was really an active question about whether civilian presidents were capable of leading America in wars and managing the military in wars...[Madison] failing badly - that set a poor first example."

But, then there was Lincoln (civilian):

"Abraham Lincoln, he had been in the Black Hawk War for a couple of months and he had been a critic," Birkner said. "And yet he proved to be an adept commander-in-chief, a very patient and effective leader on the military side."

Eisenhower (veteran):

"The typical voter seeing America stuck in the morass of Korea, they thought, 'If this guy could do D-Day, he can do Korea,' " said Birkner. "And he did. He didn't deliver a victory, but he delivered peace with honor."

And then there's this view:

Maj. Gen. Kenneth Clark, adjutant general of the National Guard, said military service is not a litmus test for him, especially since some have joined the military just to burnish their credentials for a career in politics. "It's just like degrees," he said. "Somebody's got a degree from XYZ college, it doesn't necessarily mean you learned something. It means you checked the box off."

It's clear history's lessons here are hard to pin down; different times, different people, different politics. The "veterans running for office" stories are sure to start pouring out once more local campaigns get underway in earnest.  It'll be interesting to see how much the stories are about a "vetidate's" (coining a new phrase here) experience in Iraq, and how much they look at what that person is going to do for the electorate.