Newt Gingrich raises some useful points in comparing WWII’s four years vs. the four since 9/11 [pdf]:

I appreciate the opportunity to testify today about the nation’s intelligence system and the absolute imperative for effective ongoing reform.

It is now four years and one month since the 9/11 attack on America.

The comparable date for World War II would have been January 19, 1946. By that point the United States was largely demobilizing its forces after a victorious global war.
During the comparable length of time that we have been responding to the 9/11 attacks on America, the World War II generation of Americans had rebounded from the attack on Pearl Harbor and defeated Germany, Japan and Italy, built a worldwide military and intelligence capability, built the atomic bomb, massed and organized industrial power, and laid the foundation for the worldwide network of alliances that has stabilized the world for the last sixty years.

This difference in energy, intensity, and resolve should worry all of us.

This is a fascinating topic. One thing that strikes me is how different our national awareness of the globe must have been in 1946, given millions of Americans stationed overseas. This is much different, today, I think.