The great thing about the USA is that we know how to ban IPs that come from that country. Digital financial services are not universally banned around the world.
The global online gambling industry has banned the USA for years.
If they want to exclude themselves from the global financial system, let them.
Why would you think this is only a US issue? It won't be. Not only that, many companies from different countries run their businesses such that they adhere to certain US laws even though the country they're based in don't have the same laws. How many of the masternodes will be run out of peoples homes as opposed to being hosted with some other company? How many hosting companies don't allow things like Tor nodes, adult content or anything to do with Torrents? I read somewhere today that a high number of dash masternodes are hosted with amazon. So, what happens if/when some regulations/laws are put in place where hosting companies around the world shut down any accounts that are running anything to do with virtual currency? Over the last few years, how many file sharing/download etc type sites have been shut down? I'll just put this here. Note this was a company based in Hong Kong. http://en.wikipedia.org/wiki/Megaupload