Do you think that trading is bad for Bitcoin? That somehow the US authorities have thought about how to destroy it and have struggled to come up with a better idea than "let the greedy trade it to death through volatility"? Just a thought.
IMO, trading is a net zero for BTC as a big picture. Yes, there are winners/losers, but until BTC is heavily regulated (in the future), it serves no action on the price. Bitcoinland needs massive fiat injections to bolster the price. This requires the user base per capita fiat injection to increase. The massive volatility is most likely from the buying and selling of coins on the customer level. People get scared and they dump. People get excited and they buy.
I don't think the US authorities want to destroy it, they want to see it through. In fact, I believe the front running of legislation/regulation before the infrastructure is even available supports this idea. The US stands to make a lot of money through the taxation and regulation of BTC. This could also be a new way to open commerce on a digital level. New loans/credit lines can be extended to banks and lenders and the UST can sell bonds to the Fed in exchange for worthless and overly inflated fiat to pump into its governmental programs that support digital currencies as well as commercial banks.
All of this will come full circle by BTC customers through their own acceptance (an naivety) of what this technology could, by pushing the technology as "an awesome way to pay for shit in 2015 and beyond."
That's settled a fear that I had about the US wanting it dead. I'd like to see two things in the next year or so...
1. A strong stance from the Bitcoin devs that if any outside entity tried to mess with the protocol it wouldn't happen. Even if the US pump billions into it they won't have a say. Any changes would be made purely for performance gains over the network (faster Tx etc.).
2. Adoption by some mass consumer entity, such as the McDonalds teaser that appeared on the forum today. Someone like McDonalds might "cheapen" the image of Bitcoin or have thousands of non-tech types losing coins from bungled transactions but it could be just what Bitcoin needs.