This John Frankenheimer film about a plot by the joint chiefs of staff to overthrow the president of the United States is a fascinating look at what could very easily happen if we don't maintain firm civilian control over the armed forces. The charismatic chairman of the joint chiefs played by Burt Lancaster, disagrees with the efforts of the president to bring out mutual nuclear disarmament with the Soviet Union. 

While it's fascinating to consider this story in the context of the period following the Cuban missile crisis, it's even more important today. Considering the right-wing leanings of so many in the military, and the vehement opposition to the current president by so many Americans, a similar plot today is not entirely beyond the realm of possibility.

We must remain just as vigilant of our "friends" as we are of our enemies.