I wouldn't judge the sincerity of Harrelson's anti-Persian Gulf War sentiments, but I think it's disingenuous of him to suggest that his stand was risky.
Hollywood may have "supported" the troops, but it was incorrect from the get-go to back the war. Remember the celebrity project Voices That Care?: "Stand tall, stand proud" (even though we don't think you belong over there, tra-la).
As a career move--and I'm not saying it was--Harrelson's stand was better than safe. It will serve him well. If your Calendar spread is any indication, it already has.