I believe what he's getting at is the fact that the Wikimedia Foundation's database servers all reside in St. Petersburg, and the content on them is thus subject to United States and Florida law.
My own opinion that a discussion of what it is _legal_ in the United States to advocate on userpages doesn't get us very far at all, since in most regards, the US has the strongest protection for freedom of speech in the world.
It's perfectly legal to do a lot of things that still amount to preposterous trolling that can and should cause us to ask someone to either knock off or leave the community.
We don't need to be tyrants about people's userpages. We don't need extensive rules and regulations about it. But at the same time we do need to remind people that, hey, this isn't a radical free speech zone, and really, trolling others by writing the most outrageous things is really pointless behavior.
--Jimbo