Same answer that the other gave, in my words:

Emissions are an external cost, meaning its information is lost in the price of making something.

If a country produces a lot of goods that are carbon intensive and export them, the country who import those goods cannot really calculate the carbon emission of those goods with precision. They can do estimates.

This is why accusing china of being a large emitter is wrong for several reasons:

* they are the factory of the world, they export a lot of stuff

* their emission per capita is lower compared to developed countries

Even though it's true that China could switch to nuclear energy, although they already have a lot of it.

Because in fairness, the blame for the emissions should fall on those who consume, not on those who produce. It's like blaming co2 emissions on fossil fuel companies, while you keep happily driving around your big car and flying across the world for holidays.

The consumer countries have no direct regulatory power, so they cannot force China to abide by their domestic best practices for scrubbing of flue gases, waste treatment, and other environmental considerations. There's a moral hazard involved due to our race to the bottom mentality where cheaper is always considered as better, but blame for Chinese behavior rests with China.

So pay more and manufacture at home instead of buying from China. Why blame China for your own behavior?

It seems quite clear that they are holding China responsible for its own behavior. They have the leverage to do so because China benefits from their consumer appetite.

> It's like blaming co2 emissions on fossil fuel companies

But it's not. In this scheme, the emissions get assigned to the people driving, and not to the oil companies (except the emissions produced during oil extraction).

The "don't count exports" scheme is easy to fool. Focus your economy into products that require high emissions to produce (and don't bother trying to reduce these emissions, that way you can undercut foreign markets better), export them, import low emissions products, and you get the moral high-ground that, once your exports are ignored, you're producing little emissions, even as those exports enrich you.