>If I were to shut down every bitcoin exchange (either through extreme legal, violent or economic means), I'd easily kill bitcoin overnight, mostly through destroying trust and inciting fear in adopters than from actually stopping exchange.

Like the RIAA, MPAA and US government did to bittorrent?

Yes, such an event would impact the exchange rate and perhaps even the liquidity of bitcoin to some degree, but it is not possible to destroy its utility.

I am the guy with the nuke. As a citizen of a representative democracy I would vote against any politician who favored the abolition of useful technology. Even if I disagree with the politics of that technology.