He could be a good Supreme Court justice.
Agreed, but it probably won't happen.
William Howard Taft.
Which happened over 90 years ago and Taft was the last former President to hold any office.
Even Bill Clinton, who was younger while departing the Presidency than Obama will be in 2016, had no futher political career, although I imagine it would be easy for him to become Senator or Governor if he only wanted to, given his great popularity.
Truth is, it became a strong political custom for former Presidents to stay "retired" and there is plenty of things to purse while "retired" from active politics. Carter and, to lesser degree, Clinton are best examples.
