Joining the U.S. military came with strict rules that covered citizenship, age, education, and fitness Recruiters explained that applicants needed to meet clear standards before they could enlist Officials stressed that preparation was essential, as “meeting the requirements is the first step towards serving” Joining the U.S. military comes with clear rules and expectations. Officials explained that citizenship, age, education, and physical fitness all played a role in determining eligibility. U.S. military enlistment requires citizenship or a Green Card and fluent English skills. Photo credit: Anadolu/Getty Source: Getty Images Citizenship and residency requirements U.S. citizens and some non-citizens are allowed to join the military. Non-citizens need to hold a U.S. Permanent Res...