Hey Rachel,
I live in Israel, and I think that even though my opinion probably sounds chauvinistic, it's kind of true. Soccer may be very popular for women who live in USA, but I think that it's a little weird to play soccer as a girl. Soccer is a rough sport that requires a lot of physical presence, and unless you are playing a game of 11 VS 11 girls, it will be very hard to play against a man's team, or even a mixed one.
Girls can play soccer as much as thay want, but I think as follows:
A. It's kind of weird that a girl will become a professional soccer player, because it's very competitive to marry a woman who can be stronger than you.
B. I heard an opinion that says that girls in USA are getting over excited and saying that they can win professional man teams like Manchester United and FCB (Barcelona). Girls can play soccer as long as they don't get carried away and try to compete against professional guys.
Well, to conclude, I guess soccer is a game for both guys and girls, and I think that they both can play and no one should laugh at a girl who wants to play soccer.