Ridge, who announced his resignation Tuesday, acknowledged the frustrations of working out the kinks in the broadest government reorganisation in half a century, a job critics say remains largely incomplete. "I like going to work every day," Ridge said, before adding, "There are certain days I've enjoyed it even more."

Ridge said he will remain in the job until Feb. 1, unless the Senate confirms his successor earlier.

"He was dealt an impossible hand," said Richard Clarke, the former top counter terrorism adviser to President Bush who resigned last year. "He was not allowed to make some of the key decisions about the beginning of the department. I think anyone would have failed under those circumstances."