The problem is his analysis is, well, not to the depth you would expect from a member of the academy.
When he sticks to an analysis of foreign policy, his basic assertion is that Bush's second inaugural expressed the true "Bush Doctrine", that Bush' foreign policy sought the spread of democracy despite the negative impact on international relations and public perception. He speaks as the convert who is willing to dismiss the countless examples where the reality doesn't match the rhetoric.
Gaddis' speech intrigued me at first, yet it changed from an analysis of the relationship between foreign policy statements their interpretation, and the realistic impact of the policy, to a defense of the policy based on general rhetoric that ignores the realistic implementation of the policy. If, as he asserts, the Bush doctrine is superior to the policies of other administrations for its unwillingness to abide by the existence of tyranny, the examples of U.S. supported administrations that defy basic standards of democracy are a clear and blatant counter to his thesis. Egypt and Saudi Arabia alone stand as prime counters to the idealistic glow with which Gaddis seems to view the administration's policies.
Taking a public position on policy can be very brave, yet to take a position and use demonstrably false logic is foolish.
Gaddis' endorsement of the "Bush Doctrine" will certainly create some validation, but it fails to live up to any critical analysis.