PORT-AU-PRINCE, Haiti (AP) _ American GIs may not have been happy to come to Haiti, but now many don't want to leave. And no wonder: They have been greeted as conquering heroes, hailed and cheered wherever they go.

''It's like the liberation of France, I would say, when the Americans finally got into Paris,'' observed Sgt. 1st Class Dieufort Dieujuste, a Haitian-born member of the 204th Military Police from Fort Polk, La. ''People are simply glad that we're here.''

Overjoyed would be more accurate. American military patrols can scarcely appear in public without being mobbed by gleeful, grateful crowds of Haitian civilians.

Often, the Haitians want to sell the soldiers something - wood carvings, paintings, T-shirts, maps. Or they may slip them a piece of paper bearing the name and address of a suspected ''attache,'' one of the paramilitary thugs who have terrorized people here with the tacit consent of the military government.

Often, though, they just want to see the Americans up close, to smile at them and, perhaps, to reach out and gently touch them.

Specialist Richard Novelli was on patrol outside the National Palace last week when a mob of Haitians surrounded his Humvee. ''America first 3/8'' the crowd began chanting in English. Dozens of Haitian arms reached out to touch the camouflage-green vehicle or shake hands with the soldiers. Everyone was smiling, civilians and soldiers alike.

''It's indescribable, really,'' said Novelli, a member of the 101st Military Police from Fort Campbell, Ky. ''People have been so friendly to us - it's been different.''

Different, certainly, than the mission these soldiers had trained for. When it became apparent that the mission here would be another peacekeeping mission a la Somalia, many American soldiers were disgusted.

So, too, were many members of Congress, especially Republicans. But while Congress has continued to put pressure on the Clinton administration to end the U.S. mission in Haiti, many of the soldiers here now say they should stay.

Warrant Officer Peter Riopel, a member of the 3rd Special Forces Group out of Fort Bragg, N.C., was on a Special Forces team that came to the military garrison town of Croix des Bouquets for a joint patrol with Haitian soldiers. The joint patrols are part of a plan to retrain the Haitian military.

''I'm going to tell you what the sentiments of all (U.S.) soldiers are,'' Riopel said after the patrol, standing in the shady courtyard of the garrison sipping a Pepsi. ''If you're going to put us in, let us finish the job. The United States has a habit of going in and pulling out before we finish the job. In my opinion, that hurts our credibility.''

Most soldiers seem to agree that the job isn't finished. Master Sgt. Martin Gregg, another member of the Special Forces team, said he thought the Haitian military could be reformed. But, he stressed, ''Not short-term. Anything worth doing is worth doing the right way - long-term.''

By all indications, the Pentagon is digging in for the long term. Soldiers have seen the arrival of such luxuries as hot meals, mail service and improved latrines.

The commander of U.S. forces in Haiti has opposed an early, congressionally mandated deadline. ''There's no plan to leave this job half done,'' Lt. Gen. Hugh Shelton said Friday.

One reason Shelton's troops may agree is that the mission, which was murky in its first days, has become clearer. American patrols have spread through the capital and leapfrogged about the countryside, reassuring Haitians, attempting (with limited success) to round up weapons, and arresting some of the more brazen attaches.

They also have made clear that they will not stand idly by and permit brutality by Haitian soldiers or police. In recent days, the Americans say they have experienced few problems with the Haitian military.

''They understand that their jobs are on the line, and they're willing to do whatever they can to keep them,'' observed Capt. Max Gutierrez, commanding officer of the 204th Military Police. His biggest concern - and the concern of almost everyone in the U.S. military here - is what will happen on the days surrounding the return of President Jean-Bertrand Aristide on Oct. 15.

Gutierrez has been patrolling in Petionville, the suburban home of Haiti's elite and the place where anti-American sentiment is perhaps strongest. It has been nerve-wracking, he said, but gratifying.

''I see progress each day, and that's encouraging,'' Gutierrez said.