Said The Economist: "Forget transatlantic rifts about trade, Iraq, Kyoto, or the International Criminal Court. These have been thoroughly ventilated. One area of difference has not got the attention it deserves: demography. It may prove the most important of all."
According to this report, America will overtake Europe in population by 2040 if not sooner. While U.S. fertility rates suddenly began to reverse their decline in the 1980s, continuing low European levels did not even replace current populations. While immigration fosters even further American growth, immigrants to Europe are necessary just to stay even.
Spending on defense is another point to consider. The United States already spends roughly twice as much as the entire 15-nation European Union. How much more will this be in the future if growth projections are accurate?
There is much more to the story, but one overall statement in an Economist editorial is particularly quotable: "These trends suggest that anyone who assumes the United States is now at the zenith of its economic and political power is making a big mistake." This is something to think about, although a qualifier appears in the next sentence: "There are plenty of other ways in which America could weaken itself economically or politically, but demography will offer a fine basis for future growth and strength." (Source: The Economist.)