[Sailor Steve]

In both cases you would be asserting something would happen that is extremely unlikely. The Vatican is unlikely to get rid of the office of Pope in favor of something else. This is not to say that it couldn't happen, but that it is so unlikely that there is no reason to expect that it would happen tomorrow.

Likewise the President. The procedures are set in such a way that barring the entire population agreeing to get rid of the office at the same time it just can't happen. If half the people decided it was the thing to do they would have to fight the other half. The resulting Civil War could have that outcome, but it wouldn't happen in one day, and it would take the entire population agreeing overnight for it to happen that way.

If I said that tomorrow Godzilla would attack Tokyo for real the result would be the same. It is so very unlikely that people would conclude not that it could happen, but that I was either joking or crazy. When something is beyond the realm of reasonable expectation, to claim that it will (not could, but will) happen will not only invite ridicule but said ridicule will be the only reasonable response.