Perhaps it goes without saying that a long war that demands great sacrifice from the populace, particularly one without spectacular victories to buoy the public spirit, will eventually lose support. But the Vietnam conflict did not demand half the sacrifice of World War II, for which support continued strong for the duration. In the case of Vietnam, public support, though strong in the beginning, declined rapidly later on. Why?
Student deferment—the rule that allowed college students to avoid military service—had collected young people against the war into little unsupervised enclaves. On college campuses all across the country they could commiserate together. And out of this collective commiseration came organizations such as the Students for a Democratic Society (SDS) through which students demonstrated their discomfort by making themselves obnoxious at every opportunity, thereby getting the media coverage they sought until politicians decided that there was no longer support for the continuation of the conflict. Some may contend that the SDS was not organized solely for that purpose, but if not, where is it now? It disappeared from the scene soon after we converted to an all-volunteer army.
Therefore, if and when a next time comes, student deferment, like the hiring of a substitute, must be rejected as a means of managing those who strongly object to military service.