military conscription in specific terms.
However, the 13th amendment did outlaw 'slavery and involuntary servitude' and that was used during Vietnam to fight the draft.
Forced military service is 'involuntary servitude' any way you look at it, but the courts disagreed. We need an amendment to the Constitution banning military conscription.
Free republics that only fight wars of national defense don't need miltary drafts because just like World War II, most of us would just volunteer immediately to defend the nation.