Declare War Clause

Despite widespread consensus that the Declare War Clause limits the President’s power to initiate the use of military force, it is not obvious how that limit arises from the Constitution’s text. The most common meaning of “to declare war” is to issue a formal statement called a Declaration of War that announces the new hostile relationship. Modern hostilities typically do not begin with such a statement. It is often said that the United States has fought only five “declared” wars (the War of 1812, the Mexican War, the Spanish-American War, World War I, and World War II). Others, such as the Vietnam War, are called “undeclared wars” because no such official statement was issued.

Moreover, the Framers surely understood that a formal declaration of war was not necessary prior to beginning hostilities. Eighteenth-century conflicts commonly began without formal announcements. In The Federalist No. 25, Alexander Hamilton (in a different context) observed that the formal declaration “has of late fallen into disuse.” The United States’ principal military conflicts of the immediate post-ratification period – hostilities with the Western tribes, the 1798 naval war with France, and the conflicts with the Barbary States of Algiers and Tripoli – were fought without any formal declaration.

Thus one might think the Declare War Clause refers only to official announcements of war, leaving the President with broad power to initiate “undeclared” hostilities under the executive and commander-in-chief powers. Congress could check presidential hostilities through its appropriations power, but the Declare War Clause would not have the significance often attributed to it. In modern scholarship and commentary, this is a minority view, most prominently associated with Professor John Yoo.

The narrow view of the Declare War Clause has its own difficulties, however. To begin, it is unclear why the framers would have given Congress only the narrow power to communicate about war, as the President generally is the nation’s voice in foreign affairs. Further, leading framers seemed to identify the clause as a key check on the President (which, under the narrow view, it would not be). Hamilton, for example, wrote in his first Pacificus essay (1793) that “[t]he legislature alone” can “plac[e] the nation in a state of war.” In the early post-ratification conflicts mentioned above, it was assumed that the President could not initiate hostilities without Congress’s approval, even though the conflicts were not formally declared.

The solution appears to be that by “declare war” the framers meant something broader than just formal declarations.  In the late seventeenth century, John Locke’s famous Second Treatise of Government referred to “declaring” hostile intent “by word or action.” Leading eighteenth-century writers such as Blackstone and Vattel used “declare” in a way that encompassed hostile actions as well as formal statements. Vattel, for example, wrote in The Law of Nations (1758) that “when one nation takes up arms against another, she from that moment declares herself an enemy to all individuals of the latter.” And, as Professor Saikrishna Prakash has demonstrated, eighteenth-century diplomatic and personal correspondence commonly referred to wars “declared” by hostile action. Thus the clause most likely referred to wars “declared” by attacks as well as by formal announcements.

This reading of the clause resolves the difficulties suggested above. Giving Congress the power to declare wars by word or action makes sense in the context of founding-era fears that the President would involve the nation in needless conflicts. It further explains why leading framers described the clause as an important limit on presidential war-initiation and why in post-ratification conflicts the President was understood to be so limited.

This reading also confirms a number of situations in which independent presidential actions are thought to be constitutionally permitted. The President (without Congress’s approval) cannot take actions that put the United States in a state of war – most obviously, military attacks on a foreign nation. But the clause does not bar presidential actions that do not put the United States in a state of war. Thus, for example, peacekeeping deployments and defensive deployments do not create a state of war. Similarly, rescue missions and other acts to protect U.S. citizens abroad may not create a state of war if they do not involve direct confrontation with foreign governments. It is important to note, however, that the eighteenth-century definition of “war” included low-level hostilities as well as total or full-scale conflict. Samuel Johnson’s 1755 dictionary defined war as “the exercise of violence under sovereign command.” Thus, limited hostilities with foreign nations, even if the United States is not fully engaged, would seem to require Congress’s approval.

More controversially, this reading of the Declare War Clause may allow the President considerable independent power to respond when foreign nations attack the United States. In that situation, a state of war already exists by the acts of the other side. Thus defensive responses – and perhaps even counterattacks – would not declare (initiate) war, and so would be within the President’s independent power. In 1801, Hamilton made this argument regarding the Tripoli conflict. While generally agreeing that the President could not initiate hostilities, Hamilton said that the Declare War Clause did not prevent the President from responding (including with offensive force) once Tripoli began the war. Modern commentary generally accepts this explanation of the President’s power to use defensive force in response to attacks, although it is debated whether the power goes as far as Hamilton said it did.

In sum, the best textual and historical account of the Declare War Clause is that it gives Congress exclusive power over both declaring war formally (in an official declaration of war) and declaring war informally (by authorizing hostile attacks). In its constitutional context, to “declare war” means to “initiate war.” Looking at the clause this way explains the framers’ assumption that the clause was an important limit on the President. It also suggests various situations in which the President can direct the military without specific congressional approval, because the clause is not violated when the President’s actions do not initiate war.

As Professor Ramsey cogently explains in his essay, the Declare War Clause “is not violated when the President’s actions do not initiate war.” It is also not violated when the Executive Branch uses military force (of whatever intensity) pursuant to statutory authorization; in such circumstances, the President is only carrying out authority Congress delegated pursuant to the Declare War Clause and its other war powers. That is why there is little contemporary controversy over the scope of the Declare War Clause — or its role in the separation of war powers between Congress and the Executive Branch.

Instead, most contemporary disputes between Congress and the Executive Branch over the war powers have reduced to debates over the scope of statutory authorizations that Congress has provided. And although Congress enacted the War Powers Resolution (WPR) in 1973 in an attempt to mitigate such disputes, it has thus far only served to exacerbate them, raising the question of whether there are better ways to protect the original understanding going forward.

I. Vietnam and the WPR

The War Powers Resolution was a direct response to U.S. involvement in Vietnam, which Congress initially authorized in the 1964 Gulf of Tonkin Resolution. But the scale and scope of the Vietnam conflict expanded dramatically beyond what Congress could have anticipated — with the only subsequent legislative support for the conflict coming through appropriations bills. To stem the perceived rising tide of unilateral presidential warmaking, the WPR created a framework that requires the President to report to Congress within 48 hours in any case in which U.S. armed forces are introduced “into hostilities or into situations where imminent involvement in hostilities is clearly indicated by the circumstances,” into the territory of a foreign nation for purposes other than training or supply; or “in numbers which substantially enlarge United States Armed Forces equipped for combat already located in a foreign nation.”

That report, in turn, triggers a 60-day clock (which can be extended by the President to 90 days, but no further), at the end of which the President must terminate such use of U.S. armed forces unless Congress has provided specific authorization, has extended the clock, or is unable to assemble because of an armed attack on the United States. And even before the clock has expired, the WPR gives Congress the power to terminate such uses of force pursuant to a concurrent resolution (a provision that may be unconstitutional in light of the Supreme Court’s 1983 decision in INS v. Chadha).

II. Problems With the WPR

Although the WPR was meant to cabin unilateral presidential warmaking and reassert Congress’s constitutional prerogative in the field, practice (and most academic commentary) to date suggests that it has been a spectacular failure.

First, the statutory framework does not kick in until the “clock” starts, which itself turns on when the President actually submits the report to Congress required by the statute, or when he was “required to,” whichever comes first. In practice, Congress has been reluctant to decide for itself when the clock starts, which has left the Executive Branch with at least some discretion to slow-walk the report (or not file one at all) in order to buy more time for unilateral uses of force.

Second, and related, the WPR clock turns on the existence of “hostilities,” an “ambiguous term of art,” in the words of one Executive Branch lawyer, which has been interpreted narrowly to avoid triggering the WPR framework. Thus, President Obama defended the continuing use of military force in Libya after the WPR clock expired in April 2011 on the ground that it did not constitute “hostilities,” since it was a limited mission, with limited exposure for U.S. armed forces, with very little risk of escalation, and using limited military means. The more narrowly “hostilities” can be interpreted in this manner, the more force future Presidents can engage in unilaterally without even triggering the WPR.

Third, although the WPR was meant to limit presidential warmaking, its framework all-but appears to embrace it in the short term, at least until its clock runs out. After all, by providing for the termination of military force at the end of the statutory time-period, the WPR implicitly appears to authorize such force until the termination provisions kick in, creating 60-to-90 days of authority that Congress might not otherwise have provided.

Fourth, and perhaps most significantly, the WPR says nothing about how to interpret the specific statutory authorizations that satisfy it, such as the Authorization for the Use of Military Force (AUMF) Congress enacted shortly after the September 11 attacks. Congress intended the AUMF to authorize the use of military force against those groups that were directly responsible for the September 11 attacks, but Presidents Bush and Obama subsequently interpreted its broad language to authorize force against an ever-widening array of “associated forces” of such groups, and against individuals (and in countries) with little or no connection to 9/11. The lack of specificity in the AUMF became especially apparent when the Obama administration argued that it authorized hostilities against the Islamic State in Iraq and the Levant (ISIL), a group that did not even exist on September 11 — and that was quite publicly at odds with al Qaeda, the principal perpetrators of those attacks. Whether such a reading of the AUMF was valid or not did not in any way depend upon the WPR.

III. The Future of War Powers

As a result, it seems unlikely that the War Powers Resolution will serve any salutary purpose in separating the war powers between Congress and the President going forward or in vindicating the original understanding of the Declare War Clause. And, as the AUMF debate underscores, not only will Presidents interpret statutory authorizations broadly, but Congress will be reluctant to seek their repeal. Instead, to protect the original understanding of Congress’s central institutional role in authorizing offensive uses of military force, what is needed is not another framework statute like the WPR, but rather a commitment from Congress to avoid open-ended use-of-force authorizations like the AUMF — or, at the very least, to enact them with sunsets, so that the legislature is forced to revisit such authorizations on a regular basis, and must then affirmatively undertake to reenact them, rather than repeal them.