Fifty years after the assassination of John F. Kennedy, the nation seems to be experiencing a kind of fairy tale about itself, alternately bright and dark.

It is inspiring, but also deflating, to see and hear again (and again) the handsome, vigorous president, the youngest ever elected to the office, as he beckons the country forth to the future, to the “New Frontier,” and its promise of conquest: putting a man on the moon, defeating sharply defined evils — totalitarianism, poverty, racial injustice.

This, we have been reminded, was the dream Kennedy nourished, and much of it died with him, when the sharp cracks of rifle fire broke out as his motorcade rolled through the sunstruck streets of Dallas. With this horrific, irrational deed, a curse was laid upon the land, and the people fell from grace.

But this narrative and the anniversary remembrances have obscured the deeper message sent and received on Nov. 22, 1963. In fact, America had already become a divided, dangerous place, with intimations of anarchic disorder. Beneath its gleaming surfaces, a spore had been growing, a mass of violent energies, coiled and waiting to spring.