The movie for the non-cognescenti is, of course:
The Day the Earth Stood Still,
starring Michael Rennie as Klatu, the interstellar ambassador.
Lots of sci-fi, of course, but an extremely strong message of admonition to a nation in the 50's hyped up to frenzy by the Cold War. The glactic community was fed up with dangers from the WMDs of the US and Russia, and threatened the earth with destruction if it didn't disarm. What goes around comes around.
-wg