Washington set a two term precedent; such was his stature that it was informally honored by every President until the massively egotistical Roosevelts same along. Teddy served most of McKinley's term when he was assassinated, and tried to run against his own Party for a third term and failed. His cousin FDR tried and was successful.
After the War the Republicans restored Washington's (correct) belief that one shouldn't aim to be el Presidente for life by getting the Amendment passed.
Don’t worry (or maybe you should) Rove is dancing around in the shadows starting to get Jeb Bush out there with his never say never interviews.