Trump could be elected for a third term and it could still be a temporary phenomenon, because the movement fails to transfer beyond one individual's personality.
This is incredibly complacent. The Heritage foundation view of where the US is going has been thoroughly inserted into American public life by a thorough politicisation of all public agencies. It would take an equally dominant and ruthless force to cleanse what Trump has done. I don't see that happening. Your judiciary and corporate interests have a momentum that should not be underestimated.
Breaking things is much easier than making them. American democracy is going to take a long time to recover.