WASHINGTON—Howard Lutnick’s journey from Wall Street veteran to one of President Trump’s most hawkish trade advisers began with a speech at an October campaign rally at Madison Square Garden. Lutnick extolled the virtues of tariffs and argued that the duties could at least in part replace the U.

Howard Lutnick, CEO of Wall Street brokerage firm Cantor Fitzgerald, did not address policy specifics in his written testimony for the Senate Commerce Committee seen by Reuters. As commerce secretary, Lutnick is to have "additional direct responsibility" for the U.S. Trade Representative's office.