On the last night of the Democratic National Convention, a retired Navy four-star took the stage to pay tribute to veterans. Behind him, on a giant screen, the image of four hulking warships reinforced his patriotic message.But there was a big mistake in the stirring backdrop: those are Russian warships.While retired Adm. John Nathman, a former commander of Fleet Forces Command, honored vets as America’s best, the ships from the Russian Federation Navy were arrayed like sentinels on the big screen above.These were the very Soviet-era combatants that Nathman and Cold Warriors like him had once squared off against.“The ships are definitely Russian,†said noted naval author Norman Polmar after reviewing hi-resolution photos from the event. “There’s no question of that in my mind.â€