Alaska is supposed to be the entry point for bird flu to the American hemisphere. Biologists are already at work in Alaska checking illegal immigrant birds. It was amusing to hear of the urgent preparations of a state on the east coast when bird flu is still not on the continent and will have to cross the continent to get to an eastern state.
You're right - if it comes in via migrating birds. That's the best possible case.
If it comes in via an airplane passenger in a form which is readily contagious to others, all bets are off...