What would be the effects on politics if the president was never barred from running for more than 2 terms?
Well let's see, Kennedy died, LBJ quit, Nixon resigned, Ford lost his first bid as did Carter....
Reagan began to go senile I'd say roughly by '86, and he was -for lack of a better word- tired. He's not gonna give it a go in '88.
when was he diagnosed with alzheimer's?
if he did run again, i'd expect a resignation by 1992.
I think '94, but Alzheimer's and senility are different things. Reagan was already going senile (sadly beginning while still in the Presidency -term two-), and he was going to be too old to wanna run anyway.