Final answer:
The requirement for DoD Components regarding the eligibility of homosexuals desiring to serve in the US military was established by the Department of Defense Directive 1304.26, also known as 'Don't Ask, Don't Tell' (DADT). This policy was in effect from December 1993 until a federal court ruling in July 2011 barred its enforcement and it was eventually repealed.
Step-by-step explanation:
The directive that establishes the requirement for Department of Defense (DoD) Components is known as Department of Defense Directive 1304.26 or 'Don't Ask, Don't Tell' (DADT). Enacted in December of 1993 during President Bill Clinton's administration, this policy prohibited military members from inquiring about a service member's sexual orientation. Additionally, while it allowed gay and lesbian individuals to serve, it required the dismissal of any service members who openly acknowledged their homosexuality. This directive was issued following President Clinton's unsuccessful attempt to fully lift the military ban on gay and lesbian servicemembers, which resulted in this compromise solution.
The DADT policy remained in effect until July 2011, when a federal court ruling barred its enforcement, leading to its eventual repeal. The policy was considered a controversial measure as it continued the practice of discharges based on sexual orientation despite its intention to increase inclusiveness. It's important to note that directives like Executive Order 9981, which aimed for equality in the armed services, did not specifically address sexual orientation but set a precedent for non-discrimination policies.
The Department of Defense oversees various elements of the U.S. armed forces, including the Army, Navy, Marine Corps, and Air Force, ensuring adherence to such directives until they are replaced or rescinded.