Charles Koch blasts Trump’s tariffs

Charles Koch, CEO of Koch Industries. Photo: Patrick T. Fallon for The Washington Post via Getty Images

Republican mega-donor Charles Koch lambasted President Trump's plan to impose tariffs on steel and aluminum imports, urging corporate leaders in a Washington Post op-ed Wednesday to reject the plan and arguing that it will undercut the benefits ushered in by the recent GOP tax overhaul.

Why it matters: Koch is part of a growing list of mainstream Republicans and industry leaders who are frustrated over Trump's move, yet the president has reaffirmed his plans and is expected to sign a presidential proclamation Thursday to set them in motion.