I didn't realize that people were still so aggravated about so-called draft dodgers during the Vietnam War. But since they are, this is the way I see it.
We live in a republic, a government by the people who are represented in Washington by a Congress. Under our Constitution, those representing me in Congress can declare war and draft me to fight, and I am obligated to do so. Thus World War I and World War II, right or wrong, gave us no choice because we declared war.
But fighting an undeclared, and thus illegal, war is another story, so it is up to me to decide if I want to fight in Vietnam and so become an accessory to a crime or stay home to wait until my Congress decides it is in the vital interest of the U.S. to declare war.
Simple, isn't it?