Trump says he only hires the best, but that didn't stop him from attacking his former top diplomat Friday, implying he wasn't qualified to do the job. Tillerson left the State Department in March and was replaced with Pompeo, who at the time was director of the Central Intelligence Agency.
While Tillerson had reportedly called Trump a "moron" while part of the president's cabinet, he made his views unequivocally clear Thursday when he told the CBS' "This Morning" that Trump was "pretty undisciplined" and "doesn't like to read."
Trump didn't hold back in his response, saying Tillerson "didn't have the mental capacity needed" to do the job.
Trump's tweet Friday followed a host of others addressing a wide range of topics, from the "fake news media" to Special Counsel Robert Mueller's investigation into allegations of Russian collusion in the 2016 election.
During his CBS interview, Tillerson also said that while working for the president, he often found himself having to check Trump's suggested plans of action by reminding him of the burden of legality.
"I would have to say to him: 'Mr. President I understand what you want to do but you can't do it that way. It violates the law,'" he told CBS' Bob Schieffer.