For most Americans after the Revolution, a standing army was one of the most dangerous threats to liberty. In thinking about the potential dangers of a standing army, the Founding generation had before them the precedents of Rome and England. In the first case, Julius Caesar marched his provincial army into Rome, overthrowing the power of the Senate, destroying the republic, and laying the foundation of empire. In the second, Oliver Cromwell used the army to abolish Parliament and to rule as dictator.

Under British practice, the King was not only the commander in chief; he also asserted the right to raise forces on his own. King James II, a Roman Catholic, raised a peacetime standing army and stationed it in small garrisons and camps throughout England, including one alarmingly near London. James was also suspected of building a “Catholic” army in Ireland. The threats that James’s standing armies were perceived to pose to English and Protestant institutions was a prominent cause of the dissatisfaction with James that led to the Glorious Revolution of 1688. The ensuing Bill of Rights of 1689 accordingly declared that “the raising or keeping a standing army within the kingdom in time of peace, unless it be with consent of Parliament, is against law.”

In addition, in the period leading up to the Revolution, the British Crown had forced the American colonists to quarter and otherwise support its troops. The colonists regarded the British action as being nothing other than imposing an army of occupation. The Framers were determined not to lodge the power of raising an army with the executive.

Many of the men who met in Philadelphia to draft the Constitution, however, had the experience of serving with the Continental Line, the army that ultimately bested the British for independence. Founders like George Washington, James Madison, and Alexander Hamilton were also acutely aware of the dangers external enemies posed to the new republic. The British and Spanish were not only on the frontiers of the new nation. In many cases they were within the frontiers, allying with the Indians and attempting to induce frontier settlements to split off from the country. The recent Shays’ Rebellion in Massachusetts had also impelled the Framers to consider the possibility of local rebellion.

The “raise and support Armies” clause was the Framers’ solution to the dilemma. The Constitutional Convention accepted the need for a standing army but sought to maintain control by the appropriations power of Congress, which the Founders viewed as the branch of government closest to the people.

The compromise, however, did not satisfy the Anti-Federalists. They largely shared the perspective of James Burgh, who, in his Political Disquisitions (1774), called a “standing army in times of peace, one of the most hurtful, and most dangerous of abuses.” The Anti-Federalist article “A Democratic Federalist” called a standing army “that great support of tyrants.” And Brutus, the most influential series of essays opposing ratification, argued that standing armies “are dangerous to the liberties of a people . . . not only because the rulers may employ them for the purposes of supporting themselves in any usurpation of powers, which they may see proper to exercise, but there is a great hazard, that any army will subvert the forms of government, under whose authority, they are raised, and establish one, according to the pleasure of their leader.” During the Virginia ratifying convention, George Mason exclaimed, “What havoc, desolation, and destruction, have been perpetrated by standing armies!” The Anti-Federalists would have preferred that the defense of the nation remain entirely with the state militias.

The Federalists disagreed. For them, the power of a government to raise an army was a dictate of prudence. Thus, during the Pennsylvania ratifying convention, James Wilson argued that “the power of raising and keeping up an army, in time of peace, is essential to every government. No government can secure its citizens against dangers, internal and external, without possessing it, and sometimes carrying it into execution.” In The Federalist No. 23, Hamilton argued, “These powers [of the federal government to provide for the common defense] ought to exist without limitation, because it is impossible to foresee or to define the extent and variety of national exigencies, and the correspondent extent and variety of the means which may be necessary to satisfy them.”

Nonetheless, both Federalists and Anti-Federalists alike expressed concerns about a standing army, as opposed to a navy or the militia. Accordingly, this is the only clause related to military affairs that includes a time limit on appropriations. The appropriations power of Congress is a very powerful tool, and one that the Framers saw as particularly necessary in the case of a standing army. Indeed, some individuals argued that army appropriations should be made on a yearly basis. During the Constitutional Convention, Elbridge Gerry raised precisely this point. Roger Sherman replied that the appropriations were permitted, not required, for two years. The problem, he said, was that in a time of emergency, Congress might not be in session when an annual army appropriation was needed.

The Army Clause has subtle but significant connections with other clauses of the Constitution. The Framers did not envisage that Congress would authorize a large, permanent federal land force; they believed that for most defensive purposes, the federal navy and a federalized militia would suffice. But without the availability of a standing army, presidential ambitions to win fame through military conquests in offensive wars would be checked. The Army Clause thus reinforces Congress’s authority to declare war, magnifies its power over the purse, and tends to inhibit presidential war-making. Further, the expected absence of a caste of permanent military officers stationed inside the country and comparable to Europe’s aristocracies helps sustain the “republican” nature of the American system. Finally, the Third Amendment, which requires an act of legislation before military personnel can be housed in private dwellings in wartime, raises additional hurdles for maintaining an army.

Since the time of the Constitution, legal developments based on the clause have been legislatively driven, and barely the subject of judicial interpretation. With the establishment of a federal department of defense in 1947, Army appropriations have been subsumed by a single department-wide appropriation that includes the Army, the Navy, and the Air Force (established in 1947 as part of the Army), as well as other agencies of the department. Despite periodic congressional efforts to move to a two-year appropriations cycle, the annual appropriations for the military are the rule, although not for the reasons that animated Elbridge Gerry during the Constitutional Convention. In addition, the Armed Services Committees of Congress have taken on the responsibility of authorizing almost all aspects of the defense budget as well as appropriating the funds for the services.

The character of the United States Army has changed significantly since the constitutional period in two fundamental ways. The first is its way of mobilizing. The second is its orientation and purpose.

With respect to wartime mobilization, Hamilton and later John C. Calhoun envisioned the United States Army as an “expansible” force. A small peacetime establishment would serve as the foundation for a greatly expanded force in times of emergency. The emergency ended, the citizen-soldiers would demobilize and return to their civilian occupations. With modifications, this was essentially the model for mobilization from the Mexican War through World War II.During the Cold War, the United States for the first time in its history maintained a large military establishment during peacetime. Even so, the fact that soldiers were drafted meant that citizen-soldiers continued to be the foundation of the Army. But with the end of the draft in 1973, the citizen-soldier was superseded by the long-term professional.

The draft, of course, has been a controversial issue. Although compulsory military service can be traced to the colonial and revolutionary period in America, it usually involved the states obligating service in the militia. The United States did not have a national draft until the Civil War and did not resort to a peacetime draft until 1940. Opponents of a draft have used a number of constitutional arguments in support of their position. The Supreme Court has ruled, however, that a draft is constitutional. As Chief Justice Edward White declared in The Selective Draft Law Cases (1918), “It may not be doubted that the very conception of a just government and its duty to the citizen includes the reciprocal obligation of the citizen to render military service in case of need and the right to compel it.”

The power to compel service includes a draft during peacetime, and the power to dispatch draftees overseas remains unsettled. The Seventh Circuit declared in United States v. Holmes (1967): “the power of Congress to raise armies and to take effective measures to preserve their efficiency, is not limited by the Thirteenth Amendment or the absence of a military emergency.” But according to Justice William O. Douglas dissenting from denial of certiorari in Holmes v. United States (1968), “It is clear from our decisions that conscription is constitutionally permissible when there has been a declaration of war. But we have never decided whether there may be conscription in absence of a declaration of war. Our cases suggest (but do not decide) that there may not be.”

Throughout the history of the draft, the Supreme Court has seconded Congress’s broad power to protect the selective service system, even in the face of First Amendment objections. Schenck v. United States (1919), United States v. O’Brien (1968). The draft does not intrude on the state’s right to maintain a militia, but, as the Court pointed out in The Selective Draft Law Cases, the states’ militia power can be restricted at any time by the constitutional grants of power to Congress.

Despite the Court’s affirmation of Congress’s power to institute a draft, the Court has, for some time now, been broadening exemptions to the draft, such as those with conscientious objections to war. One’s beliefs must be “sincere and meaningful,” but they do not have to be religiously based to qualify for conscientious objector status. United States v. Seeger (1965). Welsh v. United States (1970). In Gillette v. United States (1971), the Court allowed conscientious objector status to persons who had beliefs opposed to participating in armed conflict in general, but not to persons who objected only to a specific war.

In modern times, the questions of who can be a soldier and who can engage in combat have been controversial. In 1993, a Democrat-controlled Congress passed a law that codified regulations prohibiting military service for homosexuals that had been in effect before President Clinton’s inauguration. This law (10 U.S.C. § 654, included in the National Defense Authorization Act for Fiscal Year 1994, Public Law 103-160, November 30, 1993, and accompanying Senate and House report language) made the historical ban a matter of statute law. The only modification of previous regulations codified in the 1993 law was suspension of the long-standing policy of asking recruit candidates if they were homosexuals before entering service, a policy that came to be called the “don’t ask, don’t tell” compromise. In fact, the law continued to require that homosexuals, identified on the basis of acts or self-admission, must be separated from the service.

In 2010, however, Congress repealed the 1993 law, pending certification by the President, the Secretary of Defense, and the Chairman of the Joint Chiefs of Staff that military readiness would not be compromised. The certification was issued in 2011, and the ban on service by homosexuals in the military was lifted.

The congressional policy of restricting women from performing combat-related functions, though upheld as constitutional, see Rostker v. Goldberg (1981), Schlesinger v. Ballard (1975), has been gradually done away with since 1990. In 2013, Secretary of Defense Leon Panetta and the Chairman of the Joint Chiefs of Staff issued a directive permitting women to serve in front-line combat positions.

The Supreme Court has recognized that Congress’s powers to raise an army and maintain a navy extend to the military’s recruiting efforts. In opposition to the military draft of the Vietnam War, many universities prohibited the presence of military recruiters. In addition, law schools “began restricting the access of military recruiters to their students” in opposition to the military’s “don’t ask, don’t tell” policy. Rumsfeld v. Forum for Academic and Institutional Rights, Inc. (2006). In response, Congress passed and the Supreme Court upheld the Solomon Amendment, which denied federal funds to any school that refused military recruiters access.

In dicta in Rumsfeld, the Supreme Court affirmed that Congress has broad and sweeping power to raise armies and that “there is no dispute in this case that it includes the authority to require campus access for military recruiters.” The Court ultimately held that the Solomon Amendment was not an impermissible restriction because it merely requires military recruiters to be “given access to students at least equal to that ‘provided to any other employer.’” Since the repeal of “don’t ask, don’t tell,” military recruiters have largely returned to the campuses.

The purpose of the United States Army has not always been primarily to win the nation’s wars, but also to act as a constabulary. Soldiers were often used during the antebellum period to enforce the fugitive slave laws and suppress domestic violence. The Fugitive Slave Act of 1850 permitted federal marshals to call on the posse comitatus to aid in returning a slave to his owner, and Attorney General Caleb Cushing issued an opinion that included the Army in the posse comitatus.

In response, Congress enacted the Posse Comitatus Act (1878), which prohibited the use of the military to aid civil authorities in enforcing the law or suppressing civil disturbances unless expressly ordered to do so by the President. The Army welcomed the legislation. The use of soldiers as a posse removed them from their own chain of command and placed them in the uncomfortable position of taking orders from local authorities who had an interest in the disputes that provoked the unrest in the first place. As a result, many officers came to believe that the involvement of the Army in domestic policing was corrupting the institution.

In 1904, Secretary of War Elihu Root reoriented the Army away from constabulary duties to a mission focused on defeating the conventional forces of other states. This view has shaped U.S. military culture since at least World War II and continues to this day. Whether the exigencies of a modern war against terrorism once again changes the military’s mission towards domestic order is yet to be seen.