I think the reason it's discussed is "if I cannot destroy the planet in your country, I'll do that in another country (which won't change anything for the planet) where I'll go invest my money too (which means less money for your country)". And politians seem to buy on the threat, either because they truly believe it, or because they don't want to piss of the rich guys so they can get an overpaid job in one of their companies after their political career.