James Brolin is the biggest "What If" in Bond history to my eyes. We even have what were deemed successful screen tests during pre-production for
Octopussy that gives us our first big screen American Bond and preserved on celluloid. I wonder how Broccoli would have explained and retconned Bond suddenly being American but still working for British Intelligence, but then there must have been the same problems when John Gavin was cast in the role before shooting began on DAF. Twice in a twelve-year period EON Productions was working behind the scenes to give us an American James Bond but neither time was the official explanation required.
For the best, really. I like Brolin a lot but as jarring as the transition from Moore to Dalton was for so many people or even Connery to Lazenby can you imagine what an AMERICAN Bond would have done to the fanbase?