The head of NATO expressed worry that the fighting in Ukraine could spin out of control and become a war between Russia and NATO, according to an interview released Friday. “If things go wrong, they can go horribly wrong,” NATO Secretary-General Jens Stoltenberg said in remarks to Norwegian broadcaster NRK. “It is a terrible war in Ukraine. It is also a war that can become a full-fledged war that spreads into a major war between NATO and Russia,” he said. “We are working on that every day to avoid that.”