As federal unions lead the resistance to cuts by billionaire Elon Musk’s so-called Department of Government Efficiency, President Trump has pushed to end collective bargaining rights for nearly half the federal workforce in a new executive order that calls them “hostile” to his agenda. Unions say the order is the biggest attack on the labor movement in U.S. history. “It’s designed to silence workers,” says Everett Kelley, president of the American Federation of Government Employees, the largest federal employee union. He says they are also planning to join the April 5 mass rallies called by the group Indivisible.