BAGHDAD (AP) - Death squads roamed the streets, slaughtering members of the rival Muslim sect. Bombs rocked Baghdad daily - until thousands of U.S. troops poured in two years ago, establishing neighborhood bases and taking control of the Iraqi capital and other cities.

By Tuesday, all but a small number of American soldiers will have left Baghdad and other urban areas, handing over security to Iraqi soldiers and police still largely untested as an independent fighting force.

State television has been showing a countdown clock with a fluttering Iraqi flag and the words "June 30: National Sovereignty Day."

If the Iraqis can hold down violence, it will show the country is finally on the road to stability. If they fail, Iraq faces new bloodshed, straining a nation still divided along sectarian and ethnic lines.

The top U.S. commander in Iraq, Gen. Ray Odierno, said he was confident it was the right time for the move.

"I do believe they’re ready," he told CNN in an interview. "We’ve seen constant improvement in the security force, we’ve seen constant improvement in governance."

Privately, many U.S. officers worry the Iraqis will be overwhelmed if violence surges, having relied for years on the U.S. for everything from firepower to bottled water.