TOWSON, Md. — Eric Brown fights back tears. The sales lead at Apple’s Towson Town Center store stands before a crowd of union leaders, elected officials and civil rights advocates. His partner waits at home with their newborn and a toddler. Paternity leave looms. So does the loss of health insurance and a steady paycheck. “It has been hard showing up to work every day, knowing the doomsday clock has started,” Brown told the gathering on May 27. Short sentence. Heavy impact. That rally, held just steps from the store, marked the latest clash in a dispute that pits one of the world’s most valuable companies against its own retail workers. Apple plans to close the Towson location on June 20. It will shutter two other stores the same month, in Escondido, Calif., and Trumbull, Conn. The company blames declining mall conditions. Union leaders call it something else. They see targeted punishment against the first Apple retail outlet in the U.S. to organize.…