Clear evidence concerning the bias of multiple, high-ranking current and former intelligence community officials should make us think twice about letting retired intelligence officials keep access to classified information, especially if they become talking heads on television after leaving public service.

There is a great danger that vital, secret details may be revealed on television, even inadvertently.

John Brennan is no stranger to this problem.

In 2012, John Brennan leaked information to former counter-terrorism officials, who retained a security clearance, about an underwear bomb-making plot in Yemen.

Brennan revealed to these former officials - turned talking heads - that the underwear bomb plot never threatened the U.S. "because Washington had 'inside control' over it," according to Reuters.