You're using a US passport? Hand carry luggage? Maybe yes, then.
Even so, are you arriving in the morning from Asia? Beware of the scheduling that often dumps 3 or so 747s of travellers from Asia into immigration and customs all at once. You may want to sharpen your elbows.
A perfect scenario for INSPass, which, as far as I know, still hasn't been reinstalled at SFO.
Rich