When must all men register for the Selective Service?

All men are required to register for the Selective Service when they reach the age of eighteen. This registration is a federal requirement in the United States, and it is important for maintaining an updated database of individuals who could potentially be called upon for military service in the event of a national emergency. The process ensures that the government has a means of enlisting individuals to serve if the need arises.

The age of eighteen is significant because it marks the legal age of adulthood in many contexts, including voting and military service. By this age, individuals are considered mature enough to take on the responsibilities of citizenship, including the possibility of military service. The requirement to register is also part of a broader civic duty that exists within the framework of national defense.