The eruptions in the Middle East have posed perhaps the severest, most direct test yet of the limits of President Obama's signature foreign policy innovation during his first term, what the White House hails as the "light footprint" strategy.
Sensitive to public sentiment that a decade of war had debilitated America, and eager to focus on economic problems at home, President Obama quickly embraced a mix of remote-control technology and at-a-distance diplomacy to contain the most explosive problems in the Middle East, South Asia and Africa. Strikes by unmanned drone aircraft increased sixfold, secret cyberweapons were aimed at Iran, and special forces killed the world's most-wanted terrorist and made night raids the currency of American force.
For a while it worked. As Mr. Obama's newly fallen director of central intelligence, David H. Petraeus, asked so succinctly a year ago, "Who wouldn't want a light-footprint strategy?"
But implicit in Mr. Petraeus's arch question was the recognition that the strategy has limited utility. And now Mr. Obama is under more pressure than ever to become engaged in the Middle East in a way that he avoided during the presidential campaign. In his own party, there are rumblings that he should intervene more directly to halt the slaughter in Syria -- by placing Patriot missiles around the region to take down President Bashar al-Assad's air power -- and to renew efforts in the Israeli-Palestinian peace process as soon as the current missile barrages can be contained.
Overarching all those problems is the question of Iran, which has fueled the Syrian conflict in part to show that it will not sit idly while sanctions eat away at its oil revenue. Mr. Obama has already declared that he wants to start direct negotiations with Iran -- but it is a last-ditch effort, his own aides acknowledge, to avert a military confrontation that they fear could come by the middle of 2013.
Mr. Obama had hoped not to be preoccupied with these crises in the last weeks of his first term. The hope four years ago was that by now he would be reaping the peace dividends of extracting America from Iraq and withdrawing from Afghanistan, even if the mission was far from complete, so he could turn to what during the campaign he frequently characterized as "some nation-building at home."
Since 2009, Mr. Obama has tried to avoid getting sucked into the vortex of Middle Eastern conflict and dysfunction that drained so many of his predecessors. It was a deliberate choice from the start, his aides say. Fresh to the presidency, he asked his national security staff to reassess where America was overinvested and underinvested around the world.
The answer, his national security adviser, Thomas E. Donilon, recalled last week, came back quickly: "We were overweighted in some regions, such as our military commitments in the Middle East," and underweighted in regions where America's future prosperity lay, notably elsewhere in Asia.
That helps explain why Mr. Obama is moving ahead this weekend with a trip to Thailand, Myanmar and Cambodia rather than burying himself in the Situation Room in a running conference call with Prime Minister Benjamin Netanyahu of Israel and President Mohamed Morsi of Egypt, whom Mr. Obama is leaning on to contain the militant Palestinian party Hamas and stop the predictable escalation of missile attacks.
"We never considered scrapping the trip," one of Mr. Obama's top aides said on Friday. "It's the difference between keeping focused on what's important in the long term and the urgent crisis du jour, which will always be there."
To Mr. Obama's critics, the root of the seeming absence of American leverage in the Middle East today is a light footprint that was simply too light.
"I think the way to understand Obama's approach -- I wouldn't call it a strategy -- is that he has a uniform preference to keep most problems at a distance," said Eliot A. Cohen, a professor at the Johns Hopkins School of Advanced International Studies who worked for Mitt Romney's presidential campaign and helped develop Mr. Romney's critique of Mr. Obama's approach. "That is what the light footprint has been all about. And it's run out of gas."
Libya has become Exhibit 1 in that argument. Mr. Obama reluctantly committed air power to the ouster of Col. Muammar el-Qaddafi over the objections of the secretary of defense at the time, Robert M. Gates, who warned that there was no direct American interest in the outcome. Instead, the president urged the Arab League and NATO to "put skin in the game."
They did, but Mr. Obama's reluctance to put American forces on the ground during the fight, and his decision to keep America's diplomatic and C.I.A. presence minimal in post-Qaddafi Libya, may have helped lead the United States to miss signals and get caught unaware in the attack on the American mission in Benghazi. Military forces were too far from Libya's shores during the Sept. 11 attack to intervene.
At the end of the current investigations, that fact, more than any other, seems most likely to emerge as the answer to the question of why so little firepower was available to protect the ambassador and other Americans after they came under attack.
Syria has already become the next argument over the utility of the light footprint. Mr. Obama long resisted getting involved in that conflict even from the air, as he did in Libya. The international community was too disorganized; there was no NATO or Arab League effort; and the Russians and the Chinese blocked effective action at the United Nations.
Also, with the election looming, Mr. Obama had no interest in immersing America in a new war just as he was exiting two others. "We're not going to do a damn thing until the election is over," one of his senior diplomats fumed in the summer.
But with about 40,000 dead as a result of the conflict in Syria, the pressure on Mr. Obama is building, even from some Democrats. A proposal is circulating to put Patriot missile batteries in Turkey and Jordan, capable of shooting down Mr. Assad's airplanes as they attack rebel strongholds.
"It's not a fair fight," Senator Mark Udall, a Colorado Democrat, said on Saturday at the Halifax International Security Forum in Nova Scotia. "The election is over, and while I'm not endorsing a no-fly zone today, we can't stand idly by" and risk having the rest of the region inflamed.
Senator John McCain of Arizona, who ran against Mr. Obama in 2008 and has been among the most vocal advocates of greater intervention, argues that "every bad thing that we predicted would happen if we intervened -- instability in Jordan, Lebanon and Turkey -- is already happening anyway."
There seems to be no chance of an American ground intervention; even Mr. McCain, the Senate's strongest hawk, stops short of advocating that. But Mr. Obama's own aides acknowledge that his hope that he could hold back and let those with more direct interests take the lead has been dashed. The light footprint of the future may not be so light.
This article originally appeared in The New York Times.