Brennan helped establish the FBI’s counterintelligence investigation of Donald Trump’s campaign, which included the use of foreign intelligence, during the period leading up to the 2016 presidential election. Since leaving office, Brennan has been harshly critical of President Trump. In March 2018, Brennan said Trump had "paranoia", accused him of "constant misrepresentation of the facts", and described him as a "charlatan". Following the firing of FBI Deputy Director Andrew McCabe later that month, Brennan tweeted to Trump, "When the full extent of your venality, moral turpitude, and political corruption becomes known, you will take your rightful place as a disgraced demagogue in the dustbin of history. You may scapegoat Andy McCabe, but will not destroy America... America will triumph over you."