Eli Whitney – the man who perpetuated slavery. Slavery was disintegrating as an institution because it was not economically viable when Whitney’s cotton gin gave it new life. Contrast the well-meaning Eli with the irascible Henry Ford, a miserable SOB who couldn’t give a rat’s posterior about black people, but made the elevation of the lower classes possible with his process improvements. In this era of Ray Kurzweil’s insisting that advances in technology will liberate us all, it pays to remember that even clever things can have dire consequences.
Al Capone – there have been many worse criminals in American history, but Capone’s organizational skills and ruthlessness established a model that others could, and did imitate. Would another Capone have arisen to carve out a place for organised crime in America? Probably, but likely with less effect. Ethnic gangs had been long known in American cities, but the wholesale import of Old-World corruption turned out to be a weed we still can’t eradicate.
Pete Seeger -- Seeger did not much influence popular culture directly, but he was an enormous influence on Leftiedom from WWII on. He was always willing to lie for The Cause, because the true stories weren’t such good illustrations. (See, for example Waist Deep In The Big Muddy, Walkin’ Down Death Row, and I Mind My Own Business.) Seeger’s self-righteousness and genial sneers trained an entire generation of lefties in what was proper to think and what a fascist or moronic rube you were if you disagreed.
Alger Hiss – with nods to Julius and Ethel Rosenberg and Henry Wallace. With all the spite one can still generate bringing up McCarthy, Nixon, HUAC, etc, it pays to remember that there actually were traitors in our government. That they saw themselves as gentle One-Worlders does not remove the fact that they lent active support and credibility to the social system which killed 200,000,000 in the 20th C. None of them had illusions about how communists were operating worldwide, but they ignored that for the sake of a dream they wished to impose on the rest of us.
Lee Harvey Oswald – Political assassination had gone out of the American repertoire for decades until Oswald returned us to the age of anarchists with the assassination of Kennedy. This set off a string of further shootings and attempted shootings of political figures, including another Kennedy and Martin Luther King, Jr.
William March Tweed – Tammany Hall controlled the Democratic Party in New York City, and was the 800-lb gorilla of American politics for 70 years. Attempts have been made to minimize how damging this was and to paint it as a moderating influence on what could have been a more unstable situation. This is ridiculous. Corruption may be a common way station between servitude and freedom, but it is not the only way station nor a particularly good one. Boss Tweed was the sand in the gears of economic growth for decades, keeping immigrants in enslaving poverty.
The Greatest American? I’m giving the early lead to George Washington Carver. The man invented peanut butter. What tops that?