People who say that it's India, China, etc who need to sort themselves out for there to be any kind of meaningful impact are right.

But I can also imagine their argument would be that the UK population is equivalent to just two or three of their cities - if a small country like the UK can't manage anything near net zero, then why should they when it's much harder? Once the UK has walked the walk, then it can talk the talk.

The solution needs co-operation and us humans aren't great at that. It's not easy to be optimistic.