Friday’s World Cup opener against Paraguay isn’t a must-win match for the US men’s soccer team. It just can’t loseif it wants to stay in the tournament. Its own history tells it that. Since the Americans returned to the global stage three dozen years ago, whenever they’ve lost their initial Cup outing — as they did in 1990, ′98, and 2006 — they’ve gone three-and-out. When they’ve won their first match as they did in 2002 and ′14, they’ve moved on. Not without anxiety, of course.