Maybe we've simply become more aware.
CHAPTER ONE
OF DEATH AND UNREASON
It was hot; the sun was blinding; there would be a moment of cool shade ahead under the overpass they were approaching.
But the trip, until this moment, had been splendid. For the President was beginning, with this journey, the campaign of 1964—testing the politics of his leadership, and hearing the people clap in the streets.
He had just turned easily, but with grace and precision as was his style, to wave at the Texans who cheered him—when the sound rapped above the noise.
It was a blunt crack, like the sound of a motorcycle backfiring (which is what his wife thought it was), followed in about five seconds by two more; then, suddenly, the sniper’s bullets had found their mark and John Fitzgerald Kennedy lay fallen, his head in his wife’s lap.
There is amateur’s film, 400 feet long, twenty-two seconds in all, which catches alive the moment of death. The film is soundless but in color. Three motorcycle outriders come weaving around the bend, leading the black Presidential limousine; a gay patch of background frolics behind them—mint-green grasses, yellow-green foliage. The President turns in the back seat, all the way around to his right, and flings out his hand in greeting. Then the hand bends quickly up as if to touch his throat, as if something hurts. His wife, at this moment, is also leaning forward, turning to the right. Slowly he leans back to her, as if to rest his head on her shoulder. She quickly puts her arm around him, and leans even farther forward to look at him. Then, brutally, unbelievably, the head of the President is jolted by some invisible and terrible second impact. It is flung up, jerked up. An amber splash flicks in a fractional second from his head into the air. One notices the red roses spill from her lap as the President’s body topples from sight.
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Theodore H. White, The Making of the President--1964, New York, Antheneum Publishers, 1965 http://en.wikipedia.org/wiki/Theodore_White