Bottom line, as I can personally attest: Combat experience as a "grunt," albeit noble, does not necessarily provide the makings of an effective secretary of defense.
Although I disagree with much of what Bill Keller writes in his latest New York Times op-ed entitled "Chuck Hagel’s War" (http://www.nytimes.com/2013/01/21/opinion/keller-chuck-hagels-war.html?pagewanted=all&_r=0), Keller pointedly observes:
"Politicians, no less than generals, can be blinkered by experience. Vietnam made a whole generation wary of any interventions, however justified. Bill Clinton, who never fought but who was shaped by the catastrophe of Vietnam, took a lot of persuading before he did the right thing in Bosnia. He has said of his failure to send troops to stop the genocide in Rwanda that 'we just blew it.' This tendency to recoil from conflict was called 'Vietnam syndrome,' and Hagel may have the symptoms."
It is the responsibility of the secretary of defense to prepare the military to fight to the best of its ability, so as to enable the secretary of state to talk convincingly and avoid war. Or, as Teddy Roosevelt once said, "Speak softly and carry a big stick." Regrettably, the Hagel nomination has conveyed to Iran the message that Obama is backing away from a fight (see: http://jgcaesarea.blogspot.co.il/2013/01/iran-again-expresses-satisfaction-over.html), which ultimately will result in a nasty fight.
With respect to talking with your enemies, sure, it's always wise to give dialogue a chance, particularly when you carry that big stick. However, you also need to know when talk is going nowhere. The P5+1 has already talked for more than a year with Iran concerning its nuclear ambitions with no results to show for their efforts.
Chamberlain also talked with Hitler.
In addition, as I have noted in the past, it is indeed important to prevent psychopaths from obtaining Bushmasters and indulging themselves in mass murders. However, why is it that so many people who favor strict gun control don't seem to care if a rabid Iran, which hangs homosexuals, stones women to death, persecutes Baha'is, oppresses Kurds, threatens Israel with annihilation, bankrolls Bashar al-Assad and Hezbollah, and funds terrorist acts around the globe, gets hold of the bomb and holds the world hostage?
Hagel was the wrong choice.