WASHINGTON — As the war in Iraq deteriorated, a senior American intelligence analyst went public in 2005 and criticized President George W. Bush’s administration for pushing “amateurish and unrealistic” plans for the invasion two years before.

Now that same man, Gregory Hooker, is at the center of an insurrection of United States Central Command intelligence analysts over America’s latest war in Iraq, and whether Congress, policy makers and the public are being given too rosy a picture of the situation.

As the senior Iraq analyst at Central Command, the military headquarters in Tampa that oversees American military operations across the Middle East and Central Asia, Mr. Hooker is the leader of a group of analysts that is accusing senior commanders of changing intelligence reports to paint an overly optimistic portrait of the American bombing campaign against the Islamic State. The Pentagon’s inspector general is investigating.

Although the investigation became public weeks ago, the source of the allegations and Mr. Hooker’s role have not been previously known. Interviews with more than a dozen current and former intelligence officials place the dispute directly at the heart of Central Command, with Mr. Hooker and his team in a fight over what Americans should believe about the war.