IN landing more than 15,000 troops in Haiti to restore a democratically elected government, President Clinton remains on a political high wire.
The late-breaking diplomatic deal struck with the military officers running Haiti's de facto government lowers the risk to Mr. Clinton's political fortunes, just as it lowers the risk to the lives of United States troops and Haitians compared to a forced-entry invasion.
But it remains a major use of US military force. Students of how military action affects public approval of presidents tend to see very little opportunity for a lasting rally behind Clinton, but significant risk of political damage.
The conventional wisdom is that military ventures abroad cause a rallying of public support to their president. But past episodes indicate that a rallying behind the president when US soldiers are engaged in hostilities is by no means automatic.
Some military actions are unpopular, and the intervention in Haiti bears few of the features that political scientists have found typically rally public support.
``The public approves of protecting Americans, is fairly supportive of defending allies, is a bit skeptical about punishing nations in changing their policies, and the public is quite negative toward restoring order in countries when American lives are not at stake,'' according to a study by David Burbach for the Massachusetts Institute of Technology's Defense and Arms Control Studies Program.
The public also tends to judge the wisdom and competence of an intervention according to whether it succeeds, the Burbach study says.
A study by John Oneal, a University of Alabama political scientist, found that in 102 major uses of force between 1950 and 1984, the average change in popularity of the current president was zero.
In the military engagements that garnered a page-one headline in The New York Times, the average change was a gain of 1.4 percent.
MOST other studies find more positive impact than that. In the case of the Gulf war, then-President Bush gained 25 points in general approval and his ratings on every aspect of his job performance improved.
But it did not last long. Opinion of Mr. Bush's handling of the economy, for example, dropped significantly in the polls within days after the end of the war.
Rallies frequently don't occur at all, says George Edwards III, an expert on the presidency and public opinion at Texas A&M University in College Station, Texas, especially when people don't think the stakes for the country are very high, as in Haiti.
So far, Clinton has enjoyed little public support for any use of US troops in Haiti. A Time-CNN poll released Saturday showed 58 percent of Americans oppose the use of US troops while 27 percent said troops should be dispatched.
In Congress, Clinton has received strong criticism from Republicans on Haiti and only partial support from Democrats.
The timing of the military action has also raised allegations among some opponents of intervention that Clinton could be looking for a boost in popularity to help Democratic candidates at the polls.
Midterm elections in the US are just a month and a half away. President Clinton's public approval is low and his party's prospects for losing seats in Congress are high.
``If the [Haiti operation] is a disaster, then it may hurt the Democrats,'' says John Mueller, a University of Rochester political scientist and author of a key work on public opinion and war. ``If it's a success, it probably won't make much difference.''