President Trump is fanning a conspiracy theory that’s been percolating on the right. Believers think in 2016, Ukranian officials fabricated evidence about the Trump campaign to help Hillary Clinton and later kickstart the Mueller investigation. Trump also brought up that conspiracy in his July phone call with the Ukranian President, according to the rough transcript. He mentioned a cyber security company named CrowdStrike that worked with the Democratic National Committee. What is Crowdstrike, and what does it mean that the U.S. president is making national security decisions around fringe conspiracy theories?