The USA Women's National Team has probably been the number one team over the last 20 years...basically the length of time that women's soccer has had serious worldwide competitions. If not the number one team, then they certainly have been one of the dominant teams along with Norway and China.
USA have really had an advantage over other nations in their ability to constantly field strong teams year after year. Let's take a look at some of them.
In the U.S., girls play soccer just as much as boys. So they literally have millions of young girls playing organized soccer. In most other countries, it's not in their culture for girls to play what is deemed as a "man's sport". When I lived in England 20 years ago, I really don't think there were any organized teams or leagues for young girls, but when I arrived here in the U.S., there were as many girls teams as boys practically.
In the U.S. there is a progression where young girls develop from organized teams to their high school teams and then college teams. There are literally hundreds of women's college teams in the U.S. The stronger college programs treat their players almost like professionals.
The end result is that the young girls in the U.S. start playing organized soccer at a young age and then have a development structure all the way through their early 20's. Other countries simply don't have this. Other countries might or might not have organized teams for young girls, regardless, they don't have anywhere near the millions of young girls playing that the U.S. does.
So taking all that into consideration, it is no surprise that the U.S. has been one of, if not the, dominant team in Women's soccer.
Which is why I find it interesting that for the first time ever, the U.S. Women's National Team failed to automatically qualify for the World Cup...they lost in a semi final game to Mexico. Now they will still likely qualify...they beat Costa Rica in a playoff game and now have to play Italy over two legs. But it does bring up an interesting question.
Is the rest of the world catching up with the U.S. Women's National Team? And if so, why/how?