President Donald Trump has made a lot of broken promises during his time in office. He promised to lower prescription drug prices, get Mexico to pay for a border wall, and he even said a 10 percent tax cut for the middle class was on the way before the 2018 midterms. That tax cut never materialized, obviously. But the president’s latest promise might be the biggest lie of them all. Trump promised to cure cancer and eradicate AIDS if he’s re-elected in 2020.