When I was writing this post, I meant to define cosmopolitanism as something that does not take a position either way on nonhumans or future generations. Two reasons for this:
My goal was to increase self-awareness about concern for people in other countries being a distinctive feature of effective altruism. Whereas people who are especially concerned about animals or future generations tend to already be pretty self-aware that not everyone shares their position.
As Robert Wiblin noted in his summit talk, the effective altruism community does have a few people who dissent from the majority view on animals and the far future. Whereas I literally don’t know of anyone who disagrees about cosmopolitanism regarding humans.
I think the answer to your first question is mostly contained in my response to Owen. I agree that in theory cosmopolitans might disagree on immigration reform, but I chose not to talk much about it because I thought talking about cosmopolitanism and military intervention was more interesting.
For your second question, yeah, I would want to apply cosmopolitanism to cities, too. Though drill down to very small groups, and I’m less eager to take a hard stance. Bryan Caplan thinks we have special obligations to family members, but that has
Maybe I should wrap some of these comments up into a clarifying addendum.