This article seeks to explain differences between the US peace movements during the US wars in Vietnam and in Iraq. Although US public opinion has been more opposed to the Iraq war than to the Vietnam war, there has been less militant protest against the later war. In particular, there has been very little militant protest on university campuses. Several possible explanations for the difference are examined, including the absence of military conscription, disunity within the peace movement, and the end of the Cold War. The article concludes that the most significant factor has been the difference in the political situation, such that in the case of the Iraq war electoral politics seemed to most activists to offer a real hope of bringing peace.