where do your interests end?

After Hillary Clinton's announcement last week of $50 million for clean cookstoves, one New York Times reader wrote on the Dot Earth blog (comment 6)that he didn't think Americans had a moral obligation towards people living in other countries.

Dot Earth's Andrew Revkin replied

This is one of the fundamental issues of our time: Figuring out where borders of various kinds end. When your pants are made in Bangladesh, your cellphone components require minerals from gorilla habitat in Congo, your next deadly flu threat comes from a poultry/pig farm in China and your (and China’s) emissions (slowly) influence the climate and coastal future around the world, where do your interests — and responsibilities — end?