That sux....though I'm sure there are Yankee and met fans that have fought as well.
The US will not be like Europe cause the teams started as a commercial venture as opposed to a neighborhood one. There isn't the regional/tribal allegiances either.
Want to read a good book - read "How soccer explains the world" by Foer.
Seattle and Portland have a rivalry that is legit. Rivalries are building with the additions of more teams. And alcohol will usually lead to more fights.
Actually to me, soccer has arrived here, still not a top 3 sport but its here to stay. If we ever get a relegation system like in Europe then we will see even more intensity.
White people really need to get their shit together. Why arent other white people protesting in the street against this kind of crap instead of just sitting by and complaining about how they are treated as sports fans?