It shows what they are up against and a lot of the reason you get the type of deals no one liked in the healthcare bill. Sherrod Brown is really not much better than Nelson here. It was good that he pushed the case that they had to deal with tariffs for countries without carbon controls - and his pressure likely helped Kerry do what Kerry had long before spoken of as needed. (It was an issue even back in the times of Byrd/Hagel) Now, he is clearly using his vote as a lever to get more. It is not clear that they can go much further and remain WTO compliant. Brown needs to remember that Obama was originally against any tariff.
The week of June 7th should be interesting. Reid will supposedly choose between the climate bill and the energy only bill. I hope Kerry can get Obama to put some of his effort behind it - and maybe use the right name.
http://www.nytimes.com/cwire/2010/05/19/19climatewire-senate-climate-bill-in-search-of-a-few-good-20951.html