We're definitely not immune to collapse. Nuclear weapons just make things a collapse more sticky. Society needs a scapegoat to channel it's inherent violence (ie the Communists of the 50s, the "Barbarians" of Europe as you mentioned & the Terrorists of today) It's not a coincidence. Check out professor Rene Girard[1] from of Stanford if you haven't heard of him. The people who run this show know exactly what they are doing.

[1]http://www.youtube.com/results?search_query=rene+girard+scap...