While China was one of the concerns of the Kyoto Protocol that wasn't the main reason why the United States didn't participate in it. Economic factors were.
The fact is that Kyoto was just simply a bad treaty which could have been abused to punish the United States for various reasons and say that it's an enviromental issue especially since nations like Venezuela, Iran, Syria, North Korea, Cuba and other nations that participate in it which have an anti-American foreign policies to the point of rediculousness and hilarity. It excluded China and India and had side notes for other countries as well. And Russia gets to make money off of it.
Not only that it wouldn't have been ratified regardless if Bush was in office or not. The Senate overwhelmingly (95-0) voted in a response to the treaty stating that the United States should not participate in it. That's why Clinton never submitted it for ratification because it would have been easily shot down in the Senate. Bush just simply said he didn't support it and wasn't going to turn it in to the Senate for ratification.
I feel that I should stress that I feel that Bush is a horrible President, especially in regards to the enviroment. I feel that we should impliment the ideals and the measures of the Kyoto Protocol despite my opposition to the treaty. But it really isn't Bush's fault on this one