What do you call a Pope made a saint?

Is *that * what happens to Jack Ryan in the next Tom Clancy novel?
(I don’t think either Susan Saint James or Jill Saint John need to make plans, though).

Saint.

While alive and serving as Pope, by Americans, “Your Holiness Mr. President”?

Does it matter if he was a Democrat or Republican?

“… in Vatican State, office resigns You!”.

This almost never happens - and hasn’t happened since 1409, according to Wikipedia. I imagine that the “holiness”-part would be removed, but that the abdicatee would still be addressed with some form of honorific title. Just my WAG, though.