The first current or former president to speak at the third-party’s convention, Trump made several major promises to libertarians in the crowded, rowdy room, including assuring the audience that he would appoint a libertarian to his Cabinet if elected in November. But the presumptive Republican nominee also taunted the third party that has typically garnered around 1 to 3 percent of the vote in presidential races, saying they should nominate him if they want to win.