It might be due to a firewall that you're unable to connect to the server. Of course, it shouldn't matter if you connect from Europe or the USA, there are quite a few players from Europe as well.
So, check your software firewall on your computer, and make sure it doesn't block the game. Then, if you are connecting through a router, make sure the router firewall doesn't block the connection either. Open ports if that helps. Or try to connect through a VPN or proxy, but that usually makes your connection extremely slow.
