When China lined up a troupe of humanoid robots to dance in front of the German Chancellor earlier this year, a lot of people saw an impressive display of the nation’s technological prowess — but I saw something else. I’m from Texas. I know bragging when I see it. Looking beyond the robots’ footwork, China’s demonstration reveals a widening gap between spectacle and strategy — a gap that America, for all its robotics talent, is in real danger of…