In order to be considered a credible threat, you must back up your assertions with actions. Here we will look at two actions the U.S. has recently taken that would cause Iraq to consider their threats of invasion credible. The U.S. is currently attempting to get clearance from the Turkish government to deploy around 62,000 U.S. troops on Turkish soil. This would allow the U.S. to enter Kurdish-controlled northern Iraq and open a second front against Iraqi government forces in the event of a war. The U.S. military planners also say that this deployment and second front would accelerate a U.S. victory and minimize casualties. .
The U.S. is also in mass deployment of troops to the Middle-East, especially air craft carriers. As of March 1, 2003, the USS Nimitz and its battle group were assigned to the Persian Gulf. This means the U.S. military will have an unprecedented floating air force within striking distance of Iraq. After deploying the Nimitz, the U.S. will now have half of the Navy's 12 aircraft carriers massing in the Middle East. The following aircraft carriers are already in the Persian Gulf: Lincoln, the USS Kitty Hawk and the USS Constellation. The USS Harry S. Truman and USS Theodore Roosevelt are in the eastern Mediterranean, within striking range of Iraq. Each of the six carrier's air wings can hit 700 targets per day in any weather, day and night. Whether or not Turkey agrees to the U.S.'s plan, I see that action and the mass movement of aircraft carriers to the Middle East as establishing credibility to the U.S. threat of an Iraqi invasion.
