Thing1, do you really give up doing something because your neighbor won't give up doing it?
"Gee my neighbor will just keep on murdering prostitutes, so no point in me giving it up"
Have you ever read "The Sheep Looked Up"? At the end of the book, as the USA was in flames, basically an academic was asked how to cure the world of all its shortages. The answer was "Get rid of the 200 million most wasteful people on the planet, and that's happening now"....
We should absolutely commit our country to reducing carbon emissions. Can we guarantee others will go along? nope. But that's why we meet with them and discuss it and have treaties and whatnot - to try to get them to do it. China IS going into alternative energy in a big way; others will do it eventually as well. You really want to be last kid on the block to change?
Even if no one else does it, we'll be healthier, the world will be better off, and we'll have fewer expensive climate change catastrophes here.
You say it's a sacrifice - the longer we wait, the harder it will be; if we do it now, we'll have a technology leadership that will reduce the pain.