That's a valid strategy, and one the US government may even employ. However, other countries would have to agree to similar restrictions, otherwise you could trade dollars for euros, then euros for bitcoins. It also wouldn't prevent over-the-counter exchanges between individuals.
The US government would also run into opposition from groups like the EFF, and I think it would be difficult to word the law to ban bitcoins specifically, and not other similar mathematical activities (like issuing SSL certificates).
That's completely unrealistic. There is very tight cooperation between the major currency blocks when it comes to the crackdown on anonymous payments and on everything anonymous for that matter.
No there isn't. Anonymous paper money is still used in every country in the world, anonymising P2P networks like Tor and I2P have not been outlawed, you can buy pre-paid VISAs and pre-paid phones legally and anonymously and many people send routinely anonymous donations to political organisations.
you can buy pre-paid VISAs and pre-paid phones legally and anonymously
I thought legislation had been passed stating that purveyors of pre-paid debit cards and cell phones had to ask for ID and keep records so that, if the cards or phones were used in a crime, the purchaser could be traced. I do know that legislation to that effect was introduced. I'm not sure if it was ratified, but even if anonymous cards and phones are legal now, I have no confidence that they will continue to be legal for the foreseeable future.
I don't believe it was. At least, when I was in the states a few weeks back, I wasn't asked for ID when I bought a cheap pre-paid cell phone.
There is a tendency to be pessimistic about the place of anonymity in the future, but I prefer to look on the bright side. The US government doesn't win every fight it enters, and there is a long-term trend toward more freedom and openness, rather than the opposite way around.
Some things are still possible for now. Others were banned internationally (e.g anonymous savings accounts) by exerting great pressure on countries that had these things. I think the direction is clear. My prediction is that in 10 years we will not be able to even connect to the internet without authentication.
The US government would also run into opposition from groups like the EFF, and I think it would be difficult to word the law to ban bitcoins specifically, and not other similar mathematical activities (like issuing SSL certificates).