WASHINGTON — Tulsi Gabbard on Monday defended her presence at an FBI search of an election center in Fulton County, Georgia, that has raised questions about her involvement as director of national intelligence. In a letter to the top Democrats on the House and Senate intelligence committees, Gabbard said she was at the center last week in keeping with U.S. law and her responsibilities as the country’s top intelligence official. Gabbard stood by her decision not to brief lawmakers about