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He said "Yesterday." That meant any time from 1992 to the day before. Clearly, the time for invasion was over by the time Ledeen gave this answer. And now, he believes the time to attack Iran has come, where before he did not.
Thus, he can honestly say he vigorously opposes a war (or two) he strongly advocates.
You've got to be mentally nimble to be a major player in today's post-Cold War global order.