As long as people need to use USD for most purchases, then yes. As long as businesses are required to keep track of and report their earnings, then yes.

As long as the government could easily afford enough hardware to takeover the blockchain, then yes.

Taking up the sarcasm cape:

It explains the development of all the NSA datacenters lately - they want in on bitcoin mining!

> I have no doubt they could. They could pass all kinds of laws about how Bitcoin should be operated.

What they are saying is that passing laws is not an issue; the laws providing the regulatory authority have already been passed.

> Enforcing those laws is another matter.

Not really; at least, as regards the ability to engage in significant business activities that involve bitcoin.

The laws are primarily enforced with businesses, not individuals. That's why there are so few US-based bitcoin startups: operating legally means you have to become a money-transmitter and follow a ton of rules which are expensive and nullify many of Bitcoin's benefits.

I think you'll find that the US government can enforce them incredibly effectively - if you're not too big to fail.