For the White House, a Wary Wait as Syria Boils WASHINGTON - After ordering American forces to Libya last year, President Obama declared that he had tackled a humanitarian crisis more decisively than his predecessors. "When people were being brutalized in Bosnia in the 1990s," Mr. Obama told a national television audience, "it took the international community more than a year to intervene with air power to protect civilians. It took us 31 days. Yet while the Syrian government of President Bashar al-Assad has brutalized its citizens for more than a year, Mr. Obama now shows no signs of intervening with force, an option his White House sees leading only to "greater chaos, greater carnage," as Jay Carney, the press secretary, put it this week. If the president considered Libya a model of humanitarian intervention, Syria increasingly looks like Mr. Obama's Bosnia. Just as strife in the former Yugoslav republic confounded first President George Bush and then his successor, Bill Clinton, the bloody crackdown in Syria - underscored by last week's massacre of children and other villagers - has put Mr. Obama in a deeply uncomfortable position. With American troops only recently withdrawn from Iraq and still in Afghanistan, the president is loath to engage in new military actions, especially one with few advocates, even among human rights groups. And yet with each passing incident, the scale of the crisis grows. "You may come to the point where you have Srebrenica syndrome," said Edward P. Djerejian, a former ambassador to Syria, referring to the slaughter of 8,000 Bosnian Muslims that galvanized more aggressive international action in 1995. Once a humanitarian disaster looms so large, the international community becomes forced to act despite the national security considerations and the more levelheaded thinking on the consequences of military action. The White House has made clear that, however horrific, the killings in Houla last week, and another massacre discovered Wednesday, do not rise to that level. The United States has expelled the top Syrian diplomat and on Wednesday outlined more financial sanctions against Syria, but there is no serious support inside the West Wing for American military action at this point. Some officials, though, advocate arming the Syrian opposition or doing more to help others do so. Among the president's advisers, there is a recognition that the crackdown could eventually escalate to the point where it would compel a more aggressive response, but there is no consensus on what that threshold would be. One possible game-changing scenario would be the spread of the conflict beyond Syria to neighboring countries like Lebanon, Turkey or Jordan. For now, the range of options remains constrained. Every week or so, a cabinet or deputy cabinet-level meeting is convened on Syria and, much to the frustration of the participants, each time the choices on the table are more or less the same: more diplomacy, more sanctions. The latest hope is that President Vladimir V. Putin of Russia, a longtime Syrian ally, will force Mr. Assad to step down. All the military contingencies that have been developed by the Pentagon involve a serious commitment of resources, with no low-cost options as in Libya. Unlike in Libya, there is no defined rebel army holding territory that would be helped by airstrikes. Syria has a better trained, better equipped military, including Russian anti-aircraft defenses. And there is no United Nations or Arab League support for international force. "In every situation you want to do something, but the fact that you want to do something doesn't mean you will do anything," said James B. Steinberg, a former deputy secretary of state under Mr. Obama. You just have to decide even if you're motivated to do something, how far you want to go and what will work. I think in this case, the what-will-work is as important as anything else. At a time of national fatigue after a decade of war, there is not much pressure in Washington on Mr. Obama to intervene directly. But as the killing drags on with some 10,000 dead, the situation invariably plays into the developing presidential campaign. Mitt Romney, the Republican challenger, criticized Mr. Obama's leadership on Syria and supports arming the rebels. "The world looks to America to lead and we've been sitting in the back burner hoping things would become arranged in a way that was attractive to the world," Mr. Romney said in an interview broadcast Wednesday on Fox News. But frankly, what's happening in Syria is unacceptable.