The US is responsible for a
huge chunk of the historical emissions that got us to 1.5C, and on a per-capita basis US emissions still solidly outstrips China. China has only recently begun to emit any notable amount of CO2.
The western world, and Americans in particular, have made a big mess. Seems like we should focus on cleaning up our own mess before asking other people to stop their much-newer, much-smaller messmaking.