• “We are getting out.”

President Trump announced that the United States, the largest carbon polluter in history, would withdraw from the Paris climate deal.

Mr. Trump argued that the goal of reducing carbon emissions would cost the economy too much. Some U.S. states and cities, as well as business leaders, pledged to defy the decision.

An American withdrawal could take up to four years, meaning a final decision could be left to voters in the next presidential election.