The Iraq is beginning to look like a rerun of the Vietnam War, and not just because critics are crying out that the United States has again fallen into a quagmire. War opponents argue that a wartime president has overstepped his constitutional bounds and that if Congress’ constitutional role in deciding on war had been respected, the United States could have avoided trouble or at least have entered the war with broader popular support. According to Democratic Senator Edward Kennedy, the White House is improperly “abusing power, is excusing and authorizing torture, and is spying on American citizens.” The terrorists would never have been harshly interrogated and intelligence surveillance never domestically expanded if only President George W. Bush had looked to Congress.

These war critics misread the Constitution’s allocation of warmaking powers between the executive and legislative branches. Their interpretation is weakest where their case should be its strongest: who gets to decide whether to start a war. For much of the history of the nation, presidents and congresses have understood that the executive branch’s constitutional authority includes the power to begin military hostilities abroad.

Energy in the Executive

During the last two centuries, neither the president nor Congress has ever acted under the belief that the Constitution requires a declaration of war before engaging in military hostilities abroad. Although the United States has used force abroad more than 100 times, it has declared war only five times: the War of 1812, the Mexican-American and Spanish-American wars, and World War I and II. Without declarations of war or any other congressional authorization, presidents have sent troops to oppose the Russian Revolution, intervene in Mexico, fight Chinese Communists in Korea, remove Manuel Noriega from power in Panama, and prevent human rights disasters in the Balkans. Other conflicts, such as both Persian Gulf Wars, received “authorization” from Congress but not declarations of war.

Critics of these conflicts want to upend long practice by appealing to an “original understanding” of the Constitution. But the text and structure of the Constitution, as well as its application over the last two centuries, confirm that the president can begin military hostilities without the approval of Congress. The Constitution does not establish a strict warmaking process because the Framers understood that war would require the speed, decisiveness, and secrecy that only the presidency could bring. “Energy in the executive,” Alexander Hamilton argued in the Federalist Papers, “...is essential to the protection of the community against foreign attacks.” He continued, “the direction of war most peculiarly demands those qualities which distinguish the exercise of power by a single hand.”

Rather than imposing a fixed, step-by-step method for going to war, the Constitution allows the executive and legislative branches substantial flexibility in shaping the decision-making process for engaging in military hostilities. Given the increasing ability of rogue states to procure weapons of mass destruction (WMDs) and the rise of international terrorism, maintaining this flexibility is critical to preserving US national security.

The Declare War Clause

Critics of the President’s war powers appeal to an understanding of declarations probably taught in most high school civics classes. It is perhaps common sense to equate the power to “declare” war with the power to “begin” or “commence” war.

The Constitution’s Declare War Clause, however, should not be considered in isolation. In fact, the Constitution does not consistently use the word “declare” to mean “begin” or “initiate.” For instance, one constitutional provision withdraws from states the power to “engage” in war. If “declare” meant “begin” or “make,” the provision should have prohibited states from “declaring” war. Similarly, another provision defines treason as “levying War” against the United States. Again, if “declare” had the clear meaning of “begin” or “wage,” then the Constitution should have made treason the crime of “declaring war” against the United States. The evidence suggests that eighteenth-century English speakers used “engage” and “levy” broadly to include beginning or waging warfare, but not “declare,” which instead carried the connotation of the recognition of a legal status rather than of an authorization.

Aside from the constitutional text itself, the structure of several constitutional provisions suggests that declaring war does not mean the same thing as beginning, conducting, or waging war. As just mentioned, one provision generally prohibits the states from engaging in war, but it allows states to conduct hostilities if Congress approves: “No States shall, without the Consent of Congress, . . . engage in War, unless actually invaded, or in such imminent Danger as will not admit of delay.” This provision is significant because it creates the exact process that many scholars believe should govern warmaking, namely congressional preapproval with an exception for unilateral presidential response to actual attacks. If one believes that the Framers were consistent throughout the Constitution, the Framers should have written that “the President may not, without the Consent of Congress, engage in War, unless actually invaded, or in such imminent Danger as will not admit of delay.” Instead, the Constitution merely gives Congress the power to declare war and the President the power to act as Commander-in-Chief, all without any description of process.

The absence of a defined process for going to war is telling because the Constitution usually makes it very clear when it requires a specific process before the government can act. This is particularly the case when the Constitution imposes shared power on the executive and legislative branches. Article I, for example, establishes a finely tuned system of bicameralism and presentment necessary to enact federal laws. Article II, Section 2 declares that the President can make treaties subject to the advice and consent of two-thirds of the Senate while appointments can be made subject to consent of a bare majority of the Senate. Both provisions establish a process, the order in which each institution acts, and the minimum votes required. By contrast, the Constitution does not define a process for warmaking. This suggests that the absence of a defined warmaking process is an intentional element of constitutional design.

The Constitution is not merely a list of unassociated ideas; articles, sections, and even clauses often have specific functions or themes. The Declare War Clause is housed in Article I, Section 8, Clause 11. In addition to the power to declare war, that provision also vests in Congress the now-obscure powers to grant letters of marque and reprisal and to make rules concerning captures. Significantly, both of these powers relate to the recognition or declaration of a legal status rather than the authorization to carry out a specific activity. Rules on capture do not authorize captures in wartime but only determine their ownership, while letters of marque and reprisal extend the benefits of combat immunity to private forces. Reading these grouped clauses to share a common nature suggests that the Declare War Clause vested Congress with a power devoted to declarations of the international legal status of certain actions.