First, MtGox will be shut down; their bank account will be frozen and their business & owner in Japan seized
All other bank accounts involved in exchanging Bitcoins will be frozen & similar fates will occur to their proprieters
That doesn't seem to be unlikely. But I guess laws needs to be pushed towards it. And I guess few legislators would defend Bitcoin.
But what would be the reason? Ilegal trade? I guess Bitcoin may be valued without exchange for dollars. It can be used with an equivalent nominal value for goods and services without the possibility of goverment intervention.
btw, great posts guys, keep them coming.