But as “First Class” roars to its final climatic scene, it appeals to an insidious suspension of disbelief; the heroic mutants of America, bravely opposing bigotry and fear, are revealed as not so much a spectrum of humankind, but as Eagle Scouts from Mayfield. Thus, “First Class” proves itself not merely an incredible film, but an incredible work of American historical fiction. Here is a period piece for our postracial times — in the era of Ella Baker and the Rev. Dr. Martin Luther King Jr., the most powerful adversaries of spectacular apartheid are a team of enlightened white dudes. (…) When we left the theater, my son and I knew we had experienced the most thrilling movie of the summer. “First Class” is narratively lean, beautifully acted and, at all the right moments, visually stunning. But I had experienced something else. My son is 10 and a romantic, as all 10-year-olds surely have the right to be. How then do I speak to him of this world’s masterminds who render you a supporting actor in your own story? How do I speak of the Sentinels whose eyes melt history, until the world forgets that in 1962, the quintessential mutants of America were black?