Ben Shelton is the best hope for an American men’s Grand Slam champion any time soon

NEW YORK, NEW YORK - AUGUST 29: Ben Shelton of the United States reacts against Adrian Mannarino of France during their Men's Singles Third Round match on Day Six of the 2025 US Open at USTA Billie Jean King National Tennis Center on August 29, 2025 in the Flushing neighborhood of the Queens borough of New York City. (Photo by Sarah Stier/Getty Images) | Getty Images I have a theory that men’s tennis in 2026 is defined by two groups: those with superpowers, and those without.  Carlos Alcaraz…