There are, of course, large differences in approach and emphasis between Obama and Bush. Obama talks with more enthusiasm about multilateralism. This commitment, however, is yet to be seriously tested. Would Obama have stayed out of Libya if the U.N. Security Council had balked? Would he have accepted the reduction of Benghazi to ruins to demonstrate his multilateral convictions? Based on Obama’s own reasoning — that he could not “wait for the images of slaughter and mass graves before taking action” — he would have acted anyway.

It is tempting — oh so tempting — to observe that Obama is growing in office. That he is learning on the job. That he is a good note-taker, cribbing a bit here and there but finally getting his lessons down.

But this wouldn’t be fair. Obama is not copying. He is responding to a set of objective circumstances that have not changed. In the post-9/11 world, every president will seek to preempt terrorist attacks, influence the milieu that generates them and encourage the advance of hope against hatred. Perhaps it is needlessly confusing to call this the Bush Doctrine. It is, instead, a set of rather obvious strategic reactions to a continuing, undeniable threat. It is not a mystery that Obama should share these commitments — or that he should be so uncomfortable in admitting it.