This week the United States is being reminded of a truth about geopolitics: World police don't always get to control their agenda.
Take Liberia. The White House has been wary of sending troops to that battered West African nation, yet Thursday 200 Marines landed there - to inhabitants' applause.
That's not always the way it is. Remember Afghanistan? It seems ages since the US ousted its Taliban leaders. Yet the security situation today there is, if anything, worse than that in Iraq. A recent surge in violence has claimed 64 lives.
In Iraq itself, US officials are no longer talking about a relatively quick and easy exit. They're now making the point that Iraq will cost billions and require a generation-long commitment.
The bottom line: The Bush administration may be shifting back to a more reactive style of foreign policy. Two years of forceful intervention and unilateralism may have run their course.
"They have had to bend from their own rhetoric on North Korea, Liberia, and Iraq," says Ellen Laipson, a longtime government security official who now heads the Henry L. Stimson Center, a Washington think tank. "We may just be at one of those pendulum swings" that occur from time to time in world affairs.
It may be that some of the events of the day will appear less pivotal in time. Two hundred marines on the ground in Liberia is not exactly a mammoth deployment, for instance. West African regional peacekeepers form the bulk of the intervention force.
But when President Bush took office, he was of the opinion that Africa did not matter much to US national interests. Even as international pleading for a US presence in Liberia has grown in recent months, the administration has hesitated, with the Pentagon complaining that the US military is already hard pressed by existing foreign deployments.
Now a force of 2,300 marines is expected to stay afloat in the region until a United Nations operation takes over from the African-led peacekeepers. That isn't expected to happen until the fall.
Even a relatively small US commitment to Liberia may represent a change in worldview for a White House that once seemed to believe that a few areas of the world deserved intensive attention, and the rest benign neglect.
"Liberia is a good example of how sooner or later issues such as access to oil or humanitarian problems oblige rich countries to get involved in trying to put out the fires of [regional] conflicts," says Ms. Laipson.
Whether the US will now see Liberia through to stability is another question. Some critics believe that one reason the Bush administration finally acted was that with an election approaching in 18 months, the White House had to be seen as doing something.
That's something of a US pattern around the world, they say.
"That's the problem - we don't see these things through," says Pauline Baker, president of the Fund for Peace. "We just try to wipe them out of the headlines."
Meanwhile, farther eastward, Afghanistan is reeling. Two staff members of the Afghan Red Crescent were ambushed and killed on Wednesday, bringing to at least 64 the number of people killed in a 24-hour period.
The incident occurred in the Andar district of Ghazni Province, showing once again that whatever the situation in the capital city of Kabul, the situation in the hinterlands remains dangerous. NATO has now taken charge of the 5,000-strong international peacekeeping force, and some are calling for it to expand operations to more areas of the country.
In addition to the NATO force, some 12,000 US troops remain in Afghanistan, mainly to try to hunt down Taliban and Al Qaeda holdouts. In Iraq, the US reportedly will not seek a larger UN role in its occupation, but will instead try to get other nations to donate troops or money on a case-by-case basis. As it does so, the threat from followers of the former regime, international terrorists, and out-and-out criminals does not appear to be abating.
As anger among the general Iraqi population continues to simmer due to lack of electricity and other factors, it appears that the US won't be getting out soon. National Security Adviser Condoleezza Rice recently warned in a speech that rebuilding Iraq will require the same "generational commitment" that it took in Western Europe after World War II. US civilian administration Paul Bremer has said the bill for this will be in the billions.
Modern history shows that rich nations shouldn't try to run developing ones, says John Mearsheimer, political science professor at the University of Chicago. "With Iraq, Liberia, and other possible missions, the Bush administration is building an agenda that will dilute our focus," he says. "Iraq is becoming a tarpit - it will only get worse with time."
• Staff writer Abraham McLaughlin contributed to this report.