A giant computerised war game designed to test newly-built command and control systems in the region and presided over by hundreds of America's senior military officials begins in the Gulf today.
Although the game is for a classified combat scenario officials privately concede the exercises will provide a "dry run" for possible military action against Iraq.
Col Rick Thomas at Camp Doha, Kuwait, one of the key military installations which will be taking part in the exercise, said: "The computer simulations are going to teach us what to do in an actual combat situation. One possible scenario is military action against Iraq."
The exercise, codenamed Internal Look, involves 750 staff from US Central Command in Florida, who have been arriving in recent weeks at a new command centre at Al-Sayliyah, one of several new bases in the small Gulf emirate of Qatar.
They will oversee a virtual "command post exercise", with no physical troop movements but involving the biggest array of senior staff to take part in a war game outside the United States.
During the exercise, staff, led by the region's commander Gen Tommy Franks, will be linked to Bahrain, Kuwait and Saudi Arabia, where his navy, marines, air force and army commanders will be in their respective command centres by the latest communications technology.
Gen Franks is scheduled to leave the Gulf by mid-December, after the joint-service exercise ends - unless tensions with Iraq rise to the point at which the exercise is transformed into genuine war.
The notching-up of those tensions by the war game and other military exercises planned in the region over the next few weeks is, according to one military official, "the risk we have to take to see that Saddam complies with UN resolutions".
"This is all part of the psychological pressure which lets Saddam know we are ready and able to use maximum force," said the official.
But to those who monitored the events leading up to the 1991 Gulf War, in which an international force led by the United States ejected Iraqi troops from occupied Kuwait, the name Internal Look has a ominously familiar ring.
A command exercise under the same name was run by then-Central Command head Gen Norman Schwarzkopf in July 1990 to rehearse a massive US troop buildup in Saudi Arabia to defend the kingdom against an Iraqi invasion.
"It is pretty clear that we are witnessing a warm-up for war," said one western military onlooker.