There isn't because geopolitics of US pushing blame based on total instead of per capita emissions (nevermind historical) would make US look retarded - the left doesn't want that taint. Since it's not going to fly internationally, which limits it to domestic politics, and basing domestic politics of changing a geopolitical rivals largely functions as political theatre.
Just to clarify, China is at ~8T per capita [1]. USA is at 14T [2]. Rhodium group [3] says it was 10.1T and 17.6 in 2019 so it seems like the numbers have quite a bit of variability.
I do think that OP has a good point that we do probably need to consider totals since the environment doesn't care about per capita. It's also important to consider that China's energy use is probably dominated by industry supporting manufacturing for the entire world, so that "per capita" number is fairly inflated vs the true number.
The enviroment doesn't care about climate change, earth will go on in some form regardless. Climate change is an anthropocene / (geo)political problem. The only way to coordinate politcal/human problem is via metrics stakeholders think is "fair" to regulate behaviors around. Currently that's per capita, which is already concession of not factoring in historic emissions. OPs point is extra useless because it tries to coordinate geopolitics of climate change via metrics most of the world will never agree to, made even more unfeasible by trying to do so via US domestic politics. It's like suggesting PRC domestic politics should be leveraged to reduce US defense spending, it's fundmentally unworkable.
I think you're splitting hairs. Clearly "environment" in this context isn't the existence of Earth as a planet but life on Earth, the current ecology, and our place within it. That cares very much about how much total carbon output there is, regardless of what we perceive as fair. And again, as I mentioned, China's total energy use is likely artificially inflated than it might otherwise be because the world's manufacturing capacity is centered there - a fairer comparison would likely take carbon emissions used in exports and attribute that back to the home country that is importing the product. I suspect in that context USA & Europe will look remarkably worse per capita.
It may matter on academic considerations, people can discuss it, but it doesn't matter on global regulation layer whereby fairness is determined via collective consensus and for forseeable future, per capita is what everyone can live with. Your last point is signficiant because the rhetoric of total emissions isn't going to fly especially if the numbers make west look worse. In context of OPs post, trying to unilaterally frame climate debate around total emission in US and somehow turn that into geopolitcal leverage is not realistic especially if closer interogation of metric is against most major players interests. I don't think it's splitting hairs rather than acknowleding geopolitical constraints over what's workable and what's not, even if what's workable is suboptimal.
