In a sign of the times, the Federated States of Micronesia, a chain of islands in the Pacific Ocean, has lodged a legal challenge to plans to extend the life of the large Prunérov coal-fired power plant in the Czech Republic, the 11th dirtiest in Europe, an additional 25 years. Applying an established principle called transboundary harm to climate change, Micronesia argues that its very survival is jeopardized by any large power plant that doesn't curb its carbon footprint.

Environmental lawyers hope Micronesia's gambit will encourage similar challenges elsewhere. They believe the most promising method to sue American companies is the common-law doctrine of public nuisance. "Any nation could sue a U.S. company in U.S. court for a 'nuisance' caused by climate change — Tuvalu v. ExxonMobil, if you will." And if the nations were once American protectorates, such as Micronesia and Palau, they can sue American companies and governmental agencies using the Clean Air Act.

According to Matthew Pawa, one of the lead attorneys in the Kivalinaclimate change case currently before the 9th U.S. Circuit Court of Appeals, "[j]ust by bringing these cases over and over again, the judiciary [and] the public get used to the idea of [climate change] liability." As Pawa puts it, as "[c]ountries are literally being driven out of existence—they are going to turn to whatever systems they can. Right now they're looking to require developed nations to reduce emissions. In the future, I think they'll be looking for compensation."