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The site is being hosted in the US, so I'm assuming they're abiding by American laws.
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America doesn't give a shit about country borders.
If this ISIS avatar is illegal in several countries around the world, then either block those countries IP addresses from accessing this site so this guy can keep his avatar, or ban his avatar.
Wait... also ponzi schemes are illegal all over the world.. but here it's not a problem to open a thread in the investor-based games board.
What do you think about it?
I think you should find another reason , because the illegal thing doesn't work.