A quarter century after Vietnam soured America on foreign intervention, the resurgence of a United States able and willing to project military force around the globe seems complete.
For good or ill, a process that arguably started with Ronald Reagan's invasion of Grenada, and built momentum through a series of small actions and the first Gulf War, has now been capped with the toppling of an Iraqi regime long on the top of Washington's list of adversaries.
Much has been made of the Bush administration's proclamation that it will act preemptively when it feels US interests threatened. Less has been said about how, not too long ago, the larger question would have been under what circumstances America would act at all.
"We're in an entirely new strategic environment ... that requires a more forward-leaning grand strategy on the part of the US," says Robert Lieber, an expert in international theory at Georgetown University in Washington.
In some ways the trend toward a greater dependence on the military side of political-military power reached maturity during the Clinton years. The US intervention in the Balkans was a demonstration that Washington might forge ahead on its own, whatever the international consensus about use of force in a particular crisis. It was the Clinton administration that first identified Osama bin Laden as a grave threat, and attacked presumed Al Qaeda sites with cruise missiles.
But one of these sites - a factory in Sudan - may not have been linked to terrorist organizations after all. And the Clinton White House never felt the threat to be keen enough to require deployment of large numbers of US forces.
President Bush, for his part, campaigned on a platform of a more "humble" approach to military deployments. He questioned the need for nation-building and large numbers of forward-deployed US service personnel.
The realities of power changed this attitude from the first. The administration did not make much of an effort to reduce the still-considerable US presence in the Balkans, for instance. Then came Sept. 11, 2001, and a complete change in attitude toward the uses of military force abroad.
"From the 'axis of evil' speech to the actual war against Iraq, [the administration] is sending a deliberate message that was settled upon some time ago: The US does have the military power to defend itself.... And we will do that even if we have to move without the agreement of the UN and in opposition to some of our most powerful and old allies in Europe," says Andrew Hess, a professor at Tufts University's Fletcher School of Law and Diplomacy.
This new muscularity - or aggression, depending on point of view - may have already had a sobering effect on nations with which the US has long been at odds.
North Korea and Iran have been relatively quiet during the three-week Iraq war, undoubtedly pondering what all this means for them.
Other nations have become even more nervous, due to the veiled threats - opponents would say hubris - of the more hawkish Bush administration officials.
Secretary of Defense Donald Rumsfeld repeatedly warned Syria to end all aid, military and otherwise, to the regime of Saddam Hussein.
The Syrians view the US war on Iraq as irrational, says Robert Baer, a former CIA operative with more than 20 years in the Middle East and extensive contacts in Damascus. They don't believe Mr. Hussein had many terrorist ties, nor do they believe he would ever have attacked Western interests with weapons of mass destruction.
Despite its recent cooperation with the US in the search for some Al Qaeda suspects, Syria believes it fits into the same category as Iraq under Saddam Hussein, in Washington's eyes.
"Syria may be next," says Baer. "The Syrians consider it a given."
Conflict with Syria does not have to involve the 101st Airborne, point out other experts. The US will shortly control all of Iraq. Iraq shares borders with both Syria and Iran - borders that will shortly become lines of smuggling and escape, as is the border between Afghanistan and Pakistan.
"Rumsfeld has already warned Syria and Iran," says Akbar Ahmed, an expert in Islamic studies at American University. "Maybe three Middle Eastern countries will be involved [with the US military]."
The US incursion in Iraq has indeed changed the order of the world, says Akbar Ahmed, establishing a precedent for unilateral preemption that other nations might take advantage of. Will India now strike Pakistan in Kashmir, and cite the war against Hussein as inspiration?
The messages of President Bush and British Prime Minister Tony Blair to the Iraqi people promising freedom, democracy, and hope, are elegant and eloquent, says Mr. Ahmed. But the contradictions of coalition troops serving as an occupying force while trying to build indigenous institutions could strain goodwill on all sides. "How long will troops be there, stretched out? Lots of questions come up," he says.