MiB In the years leading up to WWII the US foriegn policy was isolationism. The United States tried to stay out of WWI and it tried to stay out of WWII. When it came our of WWII the US decided that it had to be more involved in foriegn affairs.
If you look at history – EVERY empire has always fallen.
The other problem is that these empires have fallen at a distinct economic point. They tend to fall when the top 10 percent of the population holds 90 percent of the wealth. I haven't been able to confirm the following statistic, but I have heard from reliable people that the US is currently at 90 percent of the wealth in the top 7 percent of the people which would indicate that the economic realities should be causing a collaps. Luckily for the US, the middle class is STILL more comfortable than any other middle class throughout history and can hold the US up. How much longer can this happen if the gap between the rich and the poor keeps expanding, and the middle class keeps diminishing?