The thing that suprised me most was the response time of the fighter planes.
The only planes available in 1933, when this movie took place, were silly, barn-storming bi-planes with an average speed of about 100 mph.
Here is the response time of those planes (From the King Kong DVD):
2.23 King Kong Breaks Chains
2.33 King Kong Is Attacked By Planes
Total time: 10 minutes
On Sept. 11, 2001, when terrorists attacked the World Trade Center and the Pentegon, modern fighter planes (F-16s), not world war one-era bi-planes, were deployed. F-16s are capable of flying over 600 miles per hour.
Here are the response times of THOSE planes (From 256.com):
08:45 Flight 11 strikes the World Trade Center's north tower at about the 80th floor.
09:49 Military F-16s arrive over Washington, D.C. to perform Combat Air Patrol over city.
Total Time: 1 Hour, 4 Minutes