Final answer:
All male citizens between 18 and 25 in the United States must register for a potential military draft.
Step-by-step explanation:
All male citizens between 18 and 25 in the United States must register for a potential military draft. The Selective Service System is responsible for maintaining a list of individuals who are eligible for military service if a draft is initiated. This requirement is based on the assumption that men are more likely to serve in combat roles, as per the traditional gender roles in the military. However, it is important to note that the draft has not been activated since 1973.
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