That's interesting .. because compliance ordered by a foreign government.. would that stand up.
Even if GLBSE got closed down as a result of investigations
initiated by US authorities, it doesn't mean they weren't breaking UK law in respect of unregistered securities. It's highly possible that the existence of GLBSE could be brought to the attention of the UK's FSA and that the FSA would take it from there without US law being involved at all.
I have no idea whether US law prevents unregistered securities being offered to US residents by foreign operators. Maybe there is some technicality which allows them to go after off-shore, unregulated exchanges even if those exchanges are legal in their local jurisdiction in the same way that they were able to go after the online poker services which were allowing US players on the technicality of transferring funds through US financial services for the purpose of online poker playing.
There are so many things affecting the value of Bitcoin "investments" at the moment that it would not be easy to establish Nefario's role in any decline in value of assets listed on GLBSE. You'd be looking at an expensive legal case, assuming that it wasn't dismissed out of hand (unlike the US, you can't "sue anyone for anything" in Commonwealth countries and lawyers themselves get sanctioned for bringing frivolous cases before the courts).