The finest steel has to go through the hottest fire, as the saying goes, and the latest round of tariffs is really cranking up the heat.On May 30 President Donald Trump fired yet another salvo in his trade war when he said that he'd double tariffs on steel imports to 50%.

President Trump's Friday announcement that steel and aluminum tariffs will double to 50% on June 4 sent shares of U.S. producers surging early Monday, including NucorNUE, Cleveland-CliffsCLF and Century AluminumCENX.