What does history tell us?

I've been reading "Remembering America: A Voice from the Sixties" by Richard Goodwin, an aide to Kennedy and Johnson. Here, with my emphases, are some excerpts from his chapter on the Bay of Pigs.

Yet that first encounter has, ever since, allowed me to understand how intelligent men, confronted with insuperable facts and arguments, despite a record of disaster heaped upon disaster, can still act as though in possession of some secret power to manipulate the destinies of men and whole nations. It is, after all, merely a subcategory of desire; the will to believe, from which none is wholly exempt, which can send men of brilliance and experience tumbling confidently toward the gale-tossed, advancing tides. It happened to the astonishing guardians of Periclean Athens, when they hurled their dwindling power against irrelevant Syracuse. It was to happen to America as it wasted the energies of a great nation - carved self-inflicted, still unhealed scars on the moment of its highest hopes - in a futile struggle over a remote stretch of populated jungle called Vietnam. And it was about to happen to John Kennedy in Cuba.

Indeed, this false certainty underlay the belief - on both sides of the Iron Curtain - that the United States and the Soviet Union were engaged in a titanic, global struggle between communism and democratic capitalism for the allegiance of the world's people. That assumption dominated, and helped explain the first of the Kennedy years; only later would it yield to a more sophisticated awareness that the multitudinous globe could not be crammed into simple categories - friends and enemies, communists or anti-communists - that the world would go its own, unforeseeable way, not on one road or two, but along a myriad of divergent paths.

That could only mean - again in retrospect - that the invaders would be met not with guns, but brass bands, enthusiastic abrazos, and banners proclaiming "Welcome to the Liberators of Cuba".

Have we learned anything in forty-five years?