On IRC, it was suggested that "the US needs exposure to sensible politics for once". I think this is a great idea, and since the US public seem to like their reality TV shows so much, here’s my suggestion:
Government Swap
For n months (where 1 < n < 12), the US government doesn’t run the US. Instead, it runs some other country, and that other country runs the US. I’m not certain exactly how much should be swapped; certainly, the Senate and House of Representatives, plus the various important-ish types (whoever’d be replaced in an election, basically). Possibly the Supreme Court, too, for good measure; can’t have them spoiling all the fun.
For best effect, I suggest switching them for the government of a country that’s actually sane. The Netherlands, maybe; I’m sure the US public would really appreciate gay marriage and (semi-)legal cannabis.