When I served in the George W. Bush administration, a group of Harley-Davidson-riding cabinet members and White House principals led the 2008 Memorial Day Rolling Thunder motorcycle parade. I own a 100th Anniversary Year Road King Classic. I am disappointed to see President Trump singling out the iconic American motorcycle company for harassment—a precedent that could inflict long-run damage on the U.S. economy.

In response to the Trump tariffs on steel and aluminum, the EU imposed a 25% tariff on American-made motorcycles....