What are your obligations if you support the war?

I teach at a conservative university. Most of my students are disengaged from politics, and most of them wholeheartedly support the war in Iraq. None of them would ever consider enlisting. The war, according to them, ought to be fought, but only by people who have "made that choice in their lives."

I'm curious to know your opinions. If you're capable of serving, is it hypocritical to favor having other people fight, but not you? Or does the fact that our military service is voluntary indeed mitigate any obligation on the part of a pro-war individual who is disinclined to take part?