The War Powers Act is a congressional resolution designed to limit the U.S. president’s ability to initiate or escalate military actions abroad. Among other restrictions, the law requires that presidents notify Congress after deploying the armed forces and limits how long units can remain engaged without congressional approval. Enacted in 1973 with the goal of avoiding another lengthy conflict such as the Vietnam War, its effectiveness has been repeatedly questioned throughout its history, and several presidents have been accused of failing to comply with its regulations.

What Is the War Powers Act?

The War Powers Act—officially called the War Powers Resolution—was enacted in November 1973 over an executive veto by President Richard M. Nixon.

The law’s text frames it as a means of guaranteeing that “the collective judgment of both the Congress and the President will apply” whenever the American armed forces are deployed overseas. To that end, it requires the President to consult with the legislature “in every possible instance” before committing troops to war.

The resolution also sets down reporting requirements for the chief executive, including the responsibility to notify Congress within 48 hours whenever military forces are introduced “into hostilities or into situations where imminent involvement in hostilities is clearly indicated by the circumstances.”

Additionally, the law stipulates that Presidents are required to end foreign military actions after 60 days unless Congress provides a declaration of war or an authorization for the operation to continue.

Origins of the War Powers Act

In the U.S. Constitution, the power to make war is shared by the executive and legislative branches. As commander-in-chief of the military, the president is charged with directing the armed forces. Congress, meanwhile, is vested with the power “to declare war” and “raise and support armies.”

These provisions were traditionally interpreted to mean that Congress had to approve American involvement in overseas wars. By the 1970s, however, many lawmakers had grown wary of presidents deploying the armed forces abroad without first consulting Congress.

President Harry S. Truman had committed U.S. troops to the Korean War as part of a United Nations “police action,” and Presidents Kennedy, Johnson and Nixon had overseen the long and controversial undeclared conflict during the Vietnam War.

Legislative efforts to reign in presidential war powers coalesced during the Nixon administration. Disturbed by revelations about the Vietnam conflict—including news that Nixon had been conducting a secret bombing campaign in Cambodia—the House and Senate crafted the War Powers Act as a means of reasserting Congressional authority over foreign wars.

Presidential Challenges

President Nixon was an early critic of the War Powers Act, and he vetoed the law on the grounds that it was an “unconstitutional and dangerous” check on his duties as commander-in-chief of the military.

In a message accompanying his veto, Nixon argued that the resolution “would attempt to take away, by a mere legislative act, authorities which the President has properly exercised under the Constitution for almost 200 years.”

Congress overrode Nixon’s veto, but he wasn’t the last chief executive to bristle at the restrictions of the War Powers Act. Since the 1970s, every sitting president has either sidestepped some of the law’s provisions or labeled it unconstitutional.

One of the first major challenges to the War Powers Act came in 1981, when President Ronald Reagan deployed military personnel to El Salvador without consulting or submitting a report to Congress. In 1999, President Bill Clinton continued a bombing campaign in Kosovo beyond the 60-day time limit cited in the law.

A more recent War Powers Act dispute arose in 2011, when President Barack Obama initiated a military action in Libya without congressional authorization.

Members of Congress have occasionally objected to the executive branch’s disregard for the War Powers Act, but attempts to take the issue to court have been unsuccessful. In 2000, for example, the Supreme Court refused to hear a case on whether the law had been violated during military operations in Yugoslavia.

Is the War Powers Act Effective?

Ever since its passage in 1973, politicians have been divided on the War Powers Act’s effectiveness. Supporters of the resolution maintain that it is a much-needed check on the president’s ability to make war without Congressional approval.

Critics, meanwhile, argue the law has failed to create better coordination between the executive and legislative branches. Some believe the law is too restrictive on the president’s ability to respond to foreign emergencies, while others contend that it gives the president free reign to commit troops overseas.

Most experts tend to agree that the War Powers Act has rarely worked as intended. According to one study by the Congressional Research Service, presidents have traditionally avoided citing certain provisions of the resolution whenever they submit reports to Congress. As a result, the 60-day time limits of the law have rarely been triggered, and it has never been used to bring an end to a foreign military operation.

Because of the War Powers Act’s contentious history, there have occasionally been calls for the resolution to be repealed or amended. One notable attempt came in 1995, when the U.S. House of Representatives voted on an amendment that would have repealed many of the Act’s main components. The measure was narrowly defeated by a vote of 217-204.

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War Powers Resolution. The Cornell Law School Legal Information Institute.
War Powers. The Law Library of Congress.
War Powers Resolution Revisited: Historic Accomplishment or Surrender? William and Mary Law Review.
War Powers Resolution: Presidential Compliance. Congressional Research Service.
The War Powers Resolution: Concepts and Practice. Congressional Research Service.