If your country is being invaded, then by all means, EVERYONE should fight. Conscription should be mandatory for any able-bodied person.

However, overseas wars that don't directly affect your nation or the homeland should be 100% voluntary. Especially if you don't agree with the politics of that war.

No matter the situation, it really is a moral issue. Sad that we cant all get along. I think no war at all would be most peoples preference.

One other thing I'd like to ad, if you're over fighting age, senior citizen, etc, you shouldn't have any say on who fights because it won't be your blood being spilt on the battlefield! Maybe with the exception of veterans that have fought in a war, because they understand the horror that will ensue for all those involved.