ONCE a war is over in the Persian Gulf, the real work begins - the delicate political effort to bring stability to an unsettled region. How much turmoil a war could leave will depend heavily on how long it lasts and how bloody it is.
While the risks are tremendous for American interests in the Middle East, optimists see an opportunity for greatly enhanced American prestige - and leverage for resolving some longstanding regional problems.
Ironically, most American experts foresee problems if the United States and its allies destroy too much of Iraq's military power.
``It's not in our interest that Iraq be dismembered,'' says Robert Neumann, former ambassador to Saudi Arabia and other Islamic countries and currently director of Middle East Studies at the Center for Strategic and International Studies. ``We need Iraq to balance the region.''
Ambassador Neumann's view is widespread in Washington. Without some military capability left in Iraq, Iran and Syria will be prone to the same sort of adventurism Iraqi President Saddam Hussein has attempted.
The US and its allies are likely to want the postwar Iraq armed, but less dangerous, than now. To maintain stability, President Bush discusses a regional security arrangement, perhaps through an international military presence.
The postwar political picture in the Middle East will be drawn according to how fast and how easily the American coalition prevails. Most forecasts fall between two scenarios, sketched by Leon Hadar, an international affairs professor at American University.
The war is over in a matter of days, with minimum casualties. Egypt, Syria, and Saudi Arabia now respect the US for its strength and reliability. Their leaders have been vindicated for aligning themselves with the West, because the alliance worked. A more moderate, less threatening, Iraqi regime takes power.
The US now has more leverage with Israel, having saved it from Saddam, to push for conciliation with moderate Arab states and perhaps even the Palestinians. Ideally, the inequities of wealth and development could be addressed in a sort of Marshall Plan for the Middle East, sponsored by Europe and Japan.
The war bogs down in trench warfare in Kuwait that goes on for months, with heavy casualties. The US gradually becomes the focus of hatred for Arabs and other Muslims, just as Saddam Hussein gains status for defiance.
The hatred blooms into ``a global and regional intifadah,'' in Dr. Hadar's term, referring to the Palestinian uprising. US embassies are burned. Terrorism is rampant. Moderate Arab regimes, such as in Egypt, are brought down. Jordan could disappear between Syrian aggression and Israeli defensiveness.
The US would have poor relations with everyone in the region but a more-isolated-than-ever Israel. With unhappy Muslim populations of their own, the Europeans and even the Soviets begin distancing themselves from American policy.
``Most depressing of all,'' says Hadar, the American public begins pressing for complete disengagement from the Middle East.
Hadar himself is not as pessimistic as his worst-case scenario, but his view falls nearer to it than to the best case. ``I don't doubt that the US can eventually defeat the Iraqis,'' he says, since the Americans wield the most advanced military machine in history. ``But I don't think it's going to be a six-day war.''
If the war is long, explains Marvin Feuerwerger, fellow at the Washington Institute for Near East Studies and a Pentagon policy planner until last summer, then anti-Americanism can begin to build. ``My sense is that if you're killing Arabs for a very long time, it begins to wear on the region,'' he says. If the war is short, he says, then US prestige in the region may not suffer.
Just back from the Middle East, however, Michael Mandelbaum of the School for Advanced International Studies at Johns Hopkins University found little concern in Arab countries about the prospect of swelling anti-Americanism or intifadah-style uprisings.
Anti-American sentiment was largely confined to Jordan, he says, and even there to Palestinians.
He found another favorable sign: Israelis are showing interest in peace initiatives after the defeat of Saddam Hussein - an interest even among members of the harder-line Likud party.
In the aftermath of war in the Gulf, pressure will be strong on the US to push for peace between Israel and the Arabs. The US cannot improve relations with Arabs without treating that urgently, Neumann says.
The Palestine Liberation Organization will be weakened by its alliance with Saddam Hussein's Iraq, he says. ``Israel can get peace from the Palestinians, but security only from its Arab neighbors,'' he says.
The key to the peace process will be Syria, Neumann says. Jordan is too weak, and Egypt has already made peace with Israel.
Americans tend to think about maintaining the post-war peace in the Gulf through NATO-style alliances or Korea-style military forces to contain the aggressive power. But the Middle East, according to many analysts of the region, is too fluid and kaleidoscopic in its political currents to treat as a fixed threat.
``There are no permanent enemies there,'' says Neumann. ``These are shifting things. It requires shifting alliances, which requires skill, not permanent structures.''
To the Bush administration, it appeared more upsetting in the region to negotiate a settlement with Saddam Hussein than to fight a war against him.
Administration officials see tremendous political cost to moderate Arab regimes from any outcome that Saddam can play as a victory. The greatest cost might be to US credibility in the region - a region that still remembers how Americans withdrew from Lebanon after Syria's invasion.
In a region where respect for strength is strong, says Mr. Feuerwerger, people remember that. ``If we fail [in Iraq], our prestige is down the tubes.''