Every war has its own rhythm in terms of how it is conducted and how the public responds. Depending on the nature of the times, the quality of political and military leadership, and the strength of the opposition, wars can go either really well or very poorly from the standpoint of achieving a country's strategic goals.

War poses a special policy challenge because it involves national security, takes place at a distance from the United States, and it evokes very strong public emotions, sometimes positive and sometimes negative. Unlike many domestic policy issues, war directly engages people in the act of government.

With the United States poised for war with Iraq, it is time to look at the history of recent American wars, from World War II (the "good" war), Vietnam (the "bad" war), and the Persian Gulf (the "fast" war). How was each conducted? What challenges arose in each case? How did the public react to the war?

After examining these examples, I discuss the case of Iraq and how it differs from past American wars. With the country divided and the international community in disagreement, Iraq is the most perplexing of our recent wars.

The Second World War was a massive activity involving over 60 different countries and more than 75 million troops of various nations (of whom 15 million were killed). Estimates place the financial cost of this war at $1 trillion, with property damage running around $230 billion.

In the 1930s, before the United States got involved in the war, public opinion was deeply ambivalent. America had a strong isolationist movement led by famed aviator Charles Lindbergh and Joseph Kennedy, among others.

However, the surprise Japanese attack on Pearl Harbor in 1941 changed public opinion. With the moral authority generated by a military attack, the American public shifted strongly in favor of war.

Even though casualties were high and nearly every family was touched by the war in some respect, the public maintained its backing of the war effort and endured rationing and other sacrifices that tested the country's spirit.

With a clearcut enemy in Germany and Japan, and opponents who were easy to demonize given atrocities that they committed, the war was framed as a good war against evil opponents. It took a number of years, but when America and its allies triumphed, it reinforced American pride in its achievement.

The United States pitched in with the Marshall plan to help rebuild Europe. Within two decades, the European economy had recovered and democratic institutions installed in Germany, Italy, and Japan. It was a fitting end to U.S. involvement with the war.

Vietnam started as a determined effort by Presidents Kennedy and Johnson to stem the tide of communism around the world. The object of the war was a small Asian country at the southern edge of China. Financed by the Russians and Chinese, the North Vietnamese were attempting to topple the South Vietnamese government supported first by France and then the United States. Their goal was to reunify their country.

In the early days, the war appeared to be going very well militarily. The public supported the policy of containing communism and fighting insurgent governments in hot spots around the globe. Pentagon body counts revealed a large number of North Vietnamese and Viet Cong troops who were being killed, seemingly a sign the war was going well. It appeared to be only a matter of time before the U.S. would win the war.

However, perplexing disparities started to arise. The American military was killing many enemy troops, but the North Vietnamese effort appeared stronger than ever. Journalists started to investigate and discovered the American military was lying about the body counts and that the war was not going well for the United States.

In the end, Vietnam proved to be no rerun of World War II. Unlike the second world war, there was moral ambiguity in Vietnam. America faced an ill-defined enemy that was hard to distinguish from civilians. There were American atrocities and massacres of unarmed civilians. It was hard to portray this war as "good" versus "evil", as had been the case during the Second World War.

As the public learned more about the war, support dropped precipitously. The country grew quite divided, and massive protests by the anti-war movement became quite prevalent. President Johnson was forced into retirement in 1968 and by 1974, the United States left Vietnam. It was a tragic ending to a very unpopular war.

One of the lessons the American military drew from Vietnam was the need for military successes to be clear and visible, and the necessity of exercising tight control over the press. With virtually unlimited press access in Vietnam (subject only to the willingness of individual reporters to risk their lives), journalists reported bad news and persuaded the general public that the war was not going well.

The Pentagon resolved never to make that mistake again. It was important to wage war quickly and show victories before negative media coverage could generate a public backlash. Only in that way could an anti-war movement be stifled and the military have time to produce a victory.

These lessons were applied with military precision during the Persian Gulf War. Before the war barely was started, the public was bombarded with military-provided video footage showing smart bombs going down the chimney of targeted buildings and blowing them up. Movements by reporters were controlled so as not to expose them to battlefield dangers. This tight control also had the virtue of monitoring how reporters did their jobs. Coverage at the front lines generally was restricted to pool coverage, whereby a few reporters were brought together to record footage and information for everyone else.

This "fast war" strategy proved to be remarkably successful in forcing Iraq out of Kuwait and back toward Baghdad. The American public reacted in a classic "rally-round-the-flag" effect and pushed President George Herbert Walker Bush's job approval numbers to nearly 90 percent, making him the most popular president in American history (until his son, George W. Bush, bested those numbers after the September 11 terrorist attacks).

The interesting question about war with Iraq is whether it will turn out to be a "good" war, a "bad" war, a "fast" war, or something completely different. As noted at the beginning of this essay, each war has its own idiosyncracies in terms of how it is conducted and the manner in which the public responds.

Notwithstanding the uncertainties surrounding Iraq, some things are clear. As of early March, the American public is significantly divided on this war. A New York Times/CBS News poll in late February found that 66 percent of Americans approved of the United States taking military action against Iraq to try to remove Saddam Hussein from power. Only 29 percent disapproved of military action and 5 percent were unsure. Women (60 percent) were less likely than men (72 percent) to approve of military action and Democrats were far less likely to support (46 percent) compared to Republicans (90 percent).

In addition, public sentiment shifts when the issue is framed as now or later. When asked in the same survey whether the United States should take military action against Iraq fairly soon, or wait and give the United Nations and weapons inspectors more time, 59 percent said more time and 37 percent preferred quick action. The survey furthermore asked whether removing Hussein from power was worth the potential loss of American life, 51 percent felt it was worth it and 40 percent did not. If military action resulted in substantial military casualties on the part of the United States, support for the war became virtually dead-even. Forty-five percent supported it, while 46 percent opposed it.

These numbers suggest divisiveness underlying American public opinion as well as citizen views around the globe. In this regard, the current situation does not differ much from public opinion in the United States during the 1930s prior to the country's entry into World War II or in 1990 before the start of the Persian Gulf War. The public almost always is ambivalent about the use of military force before war starts, but almost always turns in a supportive direction once troops are deployed and military action commences.

But how long this support stays high depends entirely on how the war goes, how many casualties there are, and how quickly troops achieve their objectives. Americans generally are able to tolerate some casualties as long as the cause is seen as just and forward momentum is maintained.

The biggest difference between Iraq and Vietnam is that the end of the Cold War means there is no super-power on the other side of the world divide prepared to send troops in to defend Iraq or provide much in the way of significant military support for Iraq. Barring that development, the United States remains the world's only super-power and in a strong position to achieve military objectives, especially given the superior state of the country's military technology.

With that power, though, comes a major responsibility to exercise force in a fair and just manner. If this century is the "American Century" as some have labeled it, it is important to govern the world in a way that does not create hatred for America or undermine support for fundamental American values, such as freedom and morality.

The other crucial variable in the conduct of the war and public response to a war is media coverage. Will reporters cover an Iraq war in the way they did World War II, Vietnam, or the Persian Gulf War? There were major differences in press response to each of these conflicts, and those differences had major ramifications for how the public came to see military action.

If the press is controlled by the military and its information limited, it will be hard for journalists who might be skeptical of military action to file stories that are critical. With network "talking heads" generally coming from a military background, media coverage in this situation would tend to be more favorable to the government and the military.

However, if a significant anti-war movement emerges, then that would be a major development for the government. The Persian Gulf War started and ended so quickly that protestors had little chance to complain and organize rallies. The result was the press paid little attention to protestors and tended to marginalize them.

For a major anti-war movement to occur, major politicians and major leaders within society would have to throw their credibility behind protests. Some Democratic presidential candidates already have taken on this role and have criticized President Bush's war plans. But it will take more than Hollywood celebrities (such as Martin Sheen) to constitute a serious threat to the administration's war plans.