Baghdad, Iraq ? International arms inspectors, “fully conscious” of their responsibility, headed out early today on their first Iraq inspections, the start of a new round whose outcome could determine the future of peace in the Middle East.

The U.N. teams drove off in a convoy of nine white four-wheel drive vehicles and vans from their headquarters on Baghdad’s outskirts toward undisclosed destinations at 8:30 a.m. local time (11:30 p.m. CST). They were expected to split into two missions today to sites previously inspected and “neutralized” in the 1990s.

The international experts face months of difficult, detailed inspections of hundreds of Iraqi sites. They must try to assess whether the Baghdad government is still committed to chemical, biological and nuclear weapons. The United States, steadily reinforcing its military might in the region, has warned it will disarm Iraq by force if the inspections fail, with or without international help.

The monitors are back after a four-year break under a mandate from the U.N. Security Council to test the Baghdad government’s contention that it has no arsenals of weapons of mass destruction, or programs to build them.

Earlier teams of U.N. experts, in seven years’ work ending in 1998, destroyed large amounts of chemical and biological armaments and longer-range missiles forbidden to Iraq by U.N. resolutions after the Gulf War, in which an Iraqi invasion force was driven from Kuwait. The inspectors also dismantled Iraq’s nuclear weapons program before it could build a bomb.

Chief U.N. inspector Hans Blix says, however, it’s “an open question” whether the Iraqis retained some weapons – especially chemical – after the 1990s round. British and U.S. leaders say they’re sure Iraq has such arms, and suspect it also is rebuilding production programs.

The U.N. inspectors are to report to the Security Council by late January on their initial round of inspections, including whether the Iraqis have been fully cooperative.

Iraq must submit a declaration by Dec. 8 detailing any such weapons programs, as well as nuclear, chemical or biological programs it claims have peaceful purposes. The Iraqis complain that this is too sweeping, encompassing even plastic slippers produced by its petrochemical industry.

If the inspectors eventually certify that Iraq has cooperated fully with their disarmament work, U.N. resolutions call for the lifting of international economic sanctions imposed on Iraq after it invaded Kuwait in 1990.

The inspections were suspended in 1998 amid disputes over U.N. access to Iraqi sites and Iraqi complaints of American spying via the U.N. operation.

The U.N. teams say they are interested in up to 900 Iraqi sites in the new inspections round.