What leaving the Paris Accord could mean for U.S. and the world

President Trump tweeted Wednesday that his decision on the Paris Accord will come “over the next few days,” an announcement that arrives after weeks of signaling he may walk away from the deal. The pact was signed in 2015 in order to reduce carbon emissions. William Brangham speaks with Princeton University's Michael Oppenheimer and Phil Kerpen of American Commitment about what's at stake.