President Donald Trump pledged to eliminate the 10 percent tariff on Irish whiskey while visiting his golf course in County Clare, Ireland. “Everybody’s been bugging me,” Mr. Trump told fans at the Amgen Irish Open, announcing the reversal. Simon Harris, the deputy prime minister of Ireland, called it a “welcome announcement of economic significance.” The move echoes a similar rollback on Scotch whisky this spring after hosting King Charles III. Mr. Trump has repeatedly used and adjusted tariff policy throughout his presidency, often based on personal interactions with foreign leaders. The announcement came during a trip that also included a controversial endorsement of Irish reunification, drawing criticism from figures like Nigel Farage and the head of the main Northern Ireland unionist party.