Why the United States needs Europe more than ever.
The United States and Europe are the best allies they've each got. Yes, they have similar traditions, share values, and have a long history of cooperation behind them. But most importantly, they are on the same side of today's geopolitical dividing line: Both are declining powers.
Although their respective declines may be happening at different speeds, there is no doubt the United States and Europe will continue to slip into irrelevance. Europe had one-quarter of the world's population in 1900, around 15 percent in 1950, and only 7 percent today. Its share is expected to go down to 5 percent by 2050. The European Union's GDP as a percentage of global GDP has shrunk from 28 percent in 1950 to 21 percent today and may be as little as 18 percent in 2050, according to internal EU documents. America's decline is not as steep, but the rapid rise of countries like China, India, and Brazil mean it will inevitably be pushed to the sidelines.