Potential White House hopeful Beto O’Rourke accused Donald Trump of fear-mongering on Monday and the Republican president mocked the Democrat as a “young man who lost” in dueling rallies that could preview the tenor of the 2020 election campaign. O’Rourke, who narrowly lost his 2018 bid for a U.S. Senate seat, accused Trump of stoking “false fear” about immigrants and telling “lies” about his hometown El Paso, which Trump said was a dangerous place before it had a border fence. “We stand for America and we stand against a wall,” O’Rourke told a crowd of several thousand supporters, many waving “Beto 2020” signs and wearing “Immigrants Make America Great” baseball caps.