The United States urged Arab ally Egypt to pull "back from the brink" after security forces killed dozens of supporters of deposed Islamist President Mohamed Mursi and opened a dangerous new phase in the army's confrontation with his Muslim Brotherhood... Washington, treading a fine line with an important Middle East ally and recipient of over $1 billion in military aid, urged the Egyptian security forces to respect the right to peaceful protest... U.S. Secretary of State John Kerry spoke to two senior members of Egypt's army-installed interim cabinet, expressing his "deep concern." "This is a pivotal moment for Egypt," he...