MtGox was a major exchange and it went down but it didn't deter people from investing in bitcoins, they merely moved their business to other exchanges.
Your original comment talked about a scenario where people decide against bitcoin and such a scenario can only play out if there is too much uncertainty to make them a viable investment. Because bitcoin is decentralized, the only way major governments can try to influence it and related activities like exchanges is by acting in concert. Anything short of this will not work against it as has happened repeatedly with past attempts by individual governments like China.
Your original comment talked about a scenario where people decide against bitcoin and such a scenario can only play out if there is too much uncertainty to make them a viable investment. Because bitcoin is decentralized, the only way major governments can try to influence it and related activities like exchanges is by acting in concert. Anything short of this will not work against it as has happened repeatedly with past attempts by individual governments like China.