The March issue of Presidential Studies Quarterly includes a series of articles placing presidential decisions for war in historical context. Following is the essay Mr. Brands wrote to introduce the series.

How do presidents decide for war? In the March issue of Presidential Studies Quarterly, editor George Edwards and I adopted a historical approach, asking experts on various past wars to analyze the decision-making process that preceded each of those conflicts. Five wars were chosen: the Spanish-American War, World War I, World War II, the Vietnam War, and the Persian Gulf War of 1991.

Other conflicts might have been selected: the War of 1812, the Mexican War, the Korean War. For balance, we could have examined crises that did not lead to regular war: the “quasi-war” with France in the late 1790s, the Venezuela controversy of 1895, the siege of Dienbienphu in 1954, the capture of the Pueblo in 1968, among many others. But limitations of space and time prevented a comprehensive treatment of decisions for—and against—war. In any event, the five conflicts chosen exhibit a broad range of the factors that enter into presidential decisions regarding war.

The Spanish-American War, the Vietnam War, and the Persian Gulf War can fairly be described as “discretionary” wars for the United States. In advance of these conflicts, American territory was not attacked or directly threatened, and American lives were endangered only incidentally. By contrast, the two world wars were “non-discretionary,” in that American lives or territory (or both) came under direct attack. For this reason—among others—the Spanish-American War, the Vietnam War, and the Persian Gulf War generated considerable controversy in the weeks surrounding the president's decision for war, while American belligerence in the two world wars was comparatively noncontroversial.

Needless to say, American definitions of security encompass more than lives and territory. American prosperity runs a close third. As John Offner shows in his piece, William McKinley worried that the turmoil in Cuba prior to the Spanish-American War would stall America's recovery from the depression of the 1890s. Kendrick Clements, in accounting for Woodrow Wilson's insistence on American neutral rights, points to the president's desire to maintain American exports. Warren Kimball stresses the American interest in open markets as an important influence in Franklin Roosevelt's decision to resist German and Japanese expansion. In my article on the Persian Gulf War, I quote James Baker as saying that the crisis in the Gulf was about “jobs.”

Political and ideological interests are also important. Wilson famously wanted to make the world “safe for democracy.” Roosevelt—with nearly all Americans—abhorred Nazi doctrine and practice on race. Lyndon Johnson, as Frederik Logevall demonstrates, defined political interests regarding Vietnam in terms both international (as they affected American credibility with allies and adversaries) and domestic (as they touched Johnson's legislative agenda). George H. W. Bush hoped the liberation of Kuwait would mark the beginning of a “new world order.”

Politics often dictated the pace at which presidents approached war. McKinley could have followed the advice of the war hawks in his administration from the beginning, but he waited until the business classes, which had hoped to avoid war, decided that the waiting was worse than the war itself would be. Wilson portrayed himself as the peace candidate until after his 1916 reelection, whereupon he moved swiftly toward war. Roosevelt similarly soft-pedaled war until after his 1940 reelection. Johnson cast Barry Goldwater as a warmonger in 1964, but then himself Americanized the war in Vietnam in 1965.

Politics partly explains why only three of the five wars studied were actually declared by Congress. McKinley, Wilson, and Roosevelt followed constitutional guidelines and historical precedent in asking Congress for a war declaration. In each case, failure to do so would have been politically dangerous, as Americans expected no less. But attitudes changed after the world entered the nuclear age. Americans understood that a war might begin and end before Congress could achieve a quorum, let alone a decision. Consequently, war-making authority largely devolved to the president as commander-in-chief. Even so, both Johnson and Bush, while denying that a congressional declaration of war was necessary, judged that its equivalent was useful. Johnson orchestrated the Gulf of Tonkin resolution, and Bush arranged congressional approval for the use of force against Iraq.

By now there is another war that might be added to the list. In the spring of 2003 George W. Bush led America to war in Iraq. Although most of the record regarding the younger Bush's decision-making remains classified, it is possible to draw some tentative conclusions regarding how he chose war—and to suggest how his decision fits into the larger pattern of presidential decisions for war. Until the terrorists attacks on New York and Washington in September 2001, neither Bush nor the American people had any demonstrable desire to go to war in the Middle East. Those attacks changed things dramatically. Bush became more bellicose, and the American people became more willing to support his bellicosity. Bush ordered a war against the Taliban in Afghanistan but increasingly directed his, and America's, attention against Iraq. He stressed the peculiar evils of the Saddam Hussein regime. He and his spokespersons strongly intimated a link between Saddam Hussein and 9/11. He and they repeatedly alleged that Iraq possessed weapons of mass destruction, which might be used against the United States. He predicted that the democratization of Iraq would lead to positive changes throughout the Middle East.

In all of this, Bush echoed arguments of earlier presidents about earlier wars. The questionable linking of Saddam Hussein to 9/11 resembled the equally tenuous connection drawn by the McKinley administration between Spain and the (probably accidental) destruction of the Maine in 1898. The emphasis on the evils of the Saddam Hussein regime reminded Americans of the evils of fascism in Roosevelt's day. The assertions of an Iraqi threat to the United States paralleled the cases made by Wilson against Germany and Roosevelt against Germany and Japan. In promoting democracy in the Middle East, Bush sounded like McKinley regarding Cuba (and then the Philippines) and Wilson regarding the world.

The five case studies focus on the decisions for war, not the conduct of war or its outcome. But because the ways wars are fought and concluded reflect the ways they begin, it might be worthwhile to say a word about whether the five presidents accomplished what they hoped. McKinley's war against Spain lasted only four months and ended in the transfer of the Philippines and Puerto Rico to the United States and the establishment of an American protectorate over Cuba. In the short term the war seemed splendidly successful. But the annexation of the Philippines led to a protracted American conflict in that archipelago, which demoralized Americans and soured them permanently on imperialism. Wilson's war against Germany lasted nineteen months and ended in an armistice that soon became a de facto German surrender. Yet the peace treaty proved disappointing, and the Senate rejected it. Before long many Americans viewed the war as a tragic mistake and vowed never to repeat the error.

World War II is the only war of the five that is still generally accounted an unqualified success, but this probably reveals less about Roosevelt's leadership than about the undeniable danger Germany and Japan posed to the United States in the early 1940s. The Vietnam War was a debacle. Johnson spoke as though communism in Southeast Asia was an imminent threat to the United States but acted as though it wasn't. He refused to choose between guns and butter, insisting on both the war and the Great Society. When the war dragged on, Americans repudiated it—and Johnson. The elder Bush's war against Iraq was swiftly successful in terms of its principal objective: the liberation of Kuwait. But the limited nature of that objective, which conspicuously did not include the overthrow of Saddam Hussein, came to seem insufficient after Saddam outlasted Bush in office. Although George W. Bush avoided language appearing to criticize his father, a common interpretation of the son's decision for war against Saddam was that he wished to finish the job his father had started.

What do the five earlier decisions for war say about the current situation in Iraq? [Editor's Note: This was written in October 2003.] Nothing definitive; the past never speaks so straightforwardly to the present. But the earlier instances do allow certain predictions. First, because no indisputable attack on the United States by Iraq preceded the war—nothing like Pearl Harbor—George W. Bush can't count on a sustained feeling of affront in the American people. So far, the weapons of mass destruction on which he rested much of his case for war haven't turned up. If they never do, the war will appear to have been as discretionary as the Spanish-American War, the Vietnam War, and the first Gulf War. Americans don't oppose discretionary wars per se, but they lose patience when such wars don't go well—as McKinley (and his successor, Theodore Roosevelt) learned in the Philippines and Johnson discovered in Vietnam. If the American occupation succeeds in delivering democracy to Iraq before American patience runs out, Bush will have accomplished—albeit on a more modest scale—what Wilson tried and failed to do, and all will be forgiven. But if Iraqi reform bogs down, he'll likely face the same kind of backlash Wilson did. And Americans may well resist future interventions, as they did for two decades after World War I and for almost that long after Vietnam.

Whatever the case studies here say—or don't say—about the current situation, they reveal much about the most important task confronting any president. Choosing between war and peace has always been the greatest responsibility of the American chief executive, and likely always will be. No topic is more worthy of careful examination.