The Selective Service System (SSS) is an independent agency of the United States government that maintains a database of registered male (as legally defined by Executive Order 14168) U.S. citizens and other U.S. residents potentially subject to military conscription (i.e., the draft).

[10] President Woodrow Wilson signed the act into law after the U.S. Army failed to meet its target of expanding to 1 million men after six weeks.

The Selective Training and Service Act of 1940 was passed by Congress on 16 September 1940, establishing the first peacetime conscription in United States history.

[17] Another four million American men called for national service were rejected for either medical or educational reasons, such as being near-sighted, having rotten teeth or being illiterate.

[19] In World War One, only the so-called "peace churches", namely the Mennonites, the Quakers and the Brethren had been allowed to reject national service on grounds of conscience.

[citation needed] The outbreak of the Korean War fostered the creation of the Universal Military Training and Service Act of 1951.

President John F. Kennedy set up Executive Order 11119 (signed on 10 September 1963), granting an exemption from conscription for married men between the ages of 19 and 26.

On 27 January 1973, Secretary of Defense Melvin Laird announced the creation of an all-volunteer armed forces, negating the need for the military draft.

[37] On 9 June 2016, a similar bill was introduced in the United States Senate, called the "Muhammad Ali Voluntary Service Act".

Miller's opinion was based on the Supreme Court's past argument in Rostker v. Goldberg (1981) which had found the male-only draft constitutional because the military then did not allow women to serve.

As the Department of Defense has since lifted most restrictions on women in the military, Miller ruled that the justifications no longer apply, and thus the act requiring only men to register would now be considered unconstitutional under the Equal Protection Clause.

An Internet meme about the event being the beginning of World War III began gaining in popularity very quickly, causing an influx of visitors to the Selective Service System website, which was not prepared to handle it.

In addition, certain categories of non-U.S. citizen men between 18 and 25 living in the United States must register, particularly permanent residents, refugees, asylum seekers, and illegal immigrants.

[3] Foreign men lawfully present in the United States who are non-immigrants, such as international students, visitors, and diplomats, are not required to register, so long as they remain in that status.

Currently, citizens who are at least 17 years and 3 months old can pre-register so when they are eligible for registration, their information will automatically be added into the system.

Some people choose to write on the registration card "I am a conscientious objector to war" to document their conviction, even though the government will not have such a classification until there is a draft.

In response, the Selective Service published plans for the "Health Care Personnel Delivery System" (HCPDS) in 1989, and has had them ready ever since.

[6][63] Selective Service bases the registration requirement on sex assigned at birth, and forces binary interpretation of this, including upon intersex individuals.

[66] In February 2019, the male-only military draft registry was ruled to be unconstitutional by a federal district judge in National Coalition for Men v. Selective Service System.

[70] In September 2021, the House of Representatives passed the National Defense Authorization Act for Fiscal Year 2022, which included an amendment that stated that "all Americans between the ages of 18 and 25 must register for selective service."

This struck off the word "Male" which extended a potential draft to women; however, the amendment was removed before the National Defense Authorization Act was passed.

Despite these possible penalties, government records indicate that from 1980 through 1986 there were only twenty indictments, of which nineteen were instigated in part by self-publicized and self-reported non-registration.

In the opinion of legal experts, this is almost impossible to prove unless there is evidence of a prospective defendant knowing about his obligation to register and intentionally choosing not to do so.

[77] Most states, as well as the District of Columbia, Guam, Northern Mariana Islands, and Virgin Islands, have passed laws requiring registration for men 18–25 to be eligible for programs that vary on a per-jurisdiction basis but typically include driver's licenses, state-funded higher education benefits, and state government jobs.

[78][79] The Department of Motor Vehicles of 27 states and 2 territories automatically register young men 18–25 with the Selective Service whenever they apply for driver licenses, learner permits, or non-driver identification cards.

[86] These challenges, however, have not been supported by the courts; as the Supreme Court stated in Butler v. Perry (1916): The amendment was adopted with reference to conditions existing since the foundation of our government, and the term 'involuntary servitude' was intended to cover those forms of compulsory labor akin to African slavery which, in practical operation, would tend to produce like undesirable results.

[88] Later, during the Vietnam War, a federal appellate court concluded in Holmes v. United States (1968) that the draft was constitutional even during peacetime.

[89] Since the reinstatement of draft registration in 1980, the Supreme Court has heard and decided four cases related to the Military Selective Service Act: Rostker v. Goldberg, 453 U.S. 57 (1981), upholding the constitutionality of requiring men but not women to register for the draft; Selective Service v. Minnesota Public Interest Research Group (MPIRG), 468 U.S. 841 (1984), upholding the constitutionality of the "Solomon Amendment", which requires applicants for Federal student aid to certify that they have complied with draft registration, either by having registered or by not being required to register; Wayte v. United States, 470 U.S. 598 (1985), upholding the policies and procedures which the Supreme Court thought the government had used to select the "most vocal" non-registrants for prosecution, after the government refused to comply with discovery orders by the trial court to produce documents and witnesses related to the selection of non-registrants for prosecution; and Elgin v. Department of Treasury, 567 U.S. 1 (2012), regarding procedures for judicial review of denial of federal employment for non-registrants.

[90] The case National Coalition for Men v. Selective Service System resulted in the male-only draft registration being declared unconstitutional by a district court.

If a draft were authorized by Congress, without any other changes being made in the law, local boards would classify registrants to determine whether they were exempt from military service.