Do you think American voters are going to be happy about sacrificing their own well-being explicitly so that other people can pollute/deforest more? Do you think that's a platform that will win elections?
Do you want a pony, too?
Look, we're not talking about straight up charity. You can talk people into charity; despite the standard narrative, the United States is quite generous in that regard. What you're asking for is for us to reduce our standard of living explicitly so other people can pollute. That's going to be a hard sell.
Every gain we make needs to unambiguously be a gain otherwise some will choose to ignore the self restriction for their own personal gain and with CO2 we all lose when that happens.