So, the oath only applies to not vetoing unconstitutional laws. The oath does not cover actual enforcement of unconstitutional laws because "he doesn't have a choice"? Why doesn't he have a choice?
You tell me, son. You're the one who brought up the oath. I know that the Constitution provides the president with the power to veto legislation he has a problem approving. A president doesn't need to sign something into law in order to get it before the Supremes.
Why don't you show me how signing a stinker of a bill compares with enforcing an existing bad law? The president can ask Congress to repeal a law he doesn't like. He can use his access to the media to explain to the citizenry why he doesn't want a law to remain on the books. He can direct his AG to mount a challenge to the law in federal court.
This is sort of senseless to discuss, though. Bush is the very last president I would expect to challenge a law such as Brady. He would have voted for it himself had he been in the Senate. He certainly would have signed it into law had it hit his desk during his term.