At the end of WWII, pretty much every other major industrial power had its industrial infrastructure in ruins. The US economy had very little competition and the world needed us to build as many good as as we possibly could.
But, it's now 60 years later. Japan and Germany have rebuilt, as have the other industrial powers. China's industry is growing, as are the industries of other, formerly undeveloped, nations.
I take it you can see why the economic situation in 2008 is different from that of 1950, right?
On top of that, half the world was engaged in that failed experiment called, "Communism."