You are assuming something that isn't true, probably based on media reports. Take Clinton - he never served and yet became President - twice. Service doesn't qualify you to be President - if it did, Reverend Wright would be president. I think it becomes a 'hot topic' when we are at war or there is a possibility of war.

It can have an effect in perception though as shown in this Pew poll:

Americans' low esteem for the federal government doesn't extend to the military. A May survey found support for the federal government the lowest in at least a decade — 37 percent — with President Bush's favorability at only 27 percent. But the survey indicated a favorability rating of 84 percent for the military.

Military service topped a list of presidential-candidate traits that would make Americans more likely to support someone in a February 2007 survey. Some 48 percent said they'd be more likely to support a candidate with military service; only 3 percent said they'd be less likely to do so.

Respondents to an April survey were asked which traits described various candidates. Ninety percent thought the word "patriotic" described McCain, while 61 percent thought it fit Obama. Seventy-one percent said "tough" fit McCain but only 49 percent applied it to Obama. Obama did better with "inspiring": 66 percent, to 39 percent for McCain

From:
http://www.mcclatchydc.com/election2008/story/42940.html

The above poll shows why minimizing McCain's service is important to the Democrats in this election. It was the opposite when Kerry was running. Both major political parties will attempt to emphasize those traits that they feel will help their candidate win. It can flip in the next election.

But, if you are really interested in a take on the effect military service has in presidential races, read this (it's short):

http://www.onebigdog.net/democrats-flip-flop-on-importance-of-military-service/

I thought it was very perceptive.


>>They will be getting over that paralysis very soon. There was a shakeup last week in McCain's campaign staff, with a Rove guy replacing the former campaign manager and some more vets from the Bush / Rove election group joining as well. These folks play to win and they will leave no card unturned, including the race card.
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>>BTW, the Wesley Clark story turns out to be more nuanced than I first thought. What he in fact said was that McCain's 6 years as a POW did not necessarily qualify him to be President. He did not criticize McCain, he just said this doesn't mean he should be President. Given how prominent the POW experience is in the narrative package McCain is presenting to voters, I don't think it was out of bounds. Clark was a military hero himself so this wasn't some cheap potshot from the peanut gallery.
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>What I don't understand, is how a military hero qualifies you to be a good president? I see this everytime in US elections.