Carly Fiorina speaks to voters last week in Greenville, S.C. (Sean Rayford/Getty Images)

I want to say something about Carly Fiorina right at the outset: I don’t care if she was a brilliant or awful chief executive of Hewlett-Packard. I don’t care if her firing was justified or the work of mean old men. I don’t care if she increased cash flow and doubled revenues or whether those are misleading indicators — which, as it happens, they are. What matters most is that being a CEO has nothing to do with being president.

You can scan the list of 20th- and 21st-century presidents and find exactly one who made his rep as a businessman. The exception was the hapless Herbert Hoover, who earned a fortune as a mining engineer, ran his own companies all over the world and successfully organized a huge effort to bring relief to Europe following World War I. He was a man of astonishing abilities — except in politics. His presidency was a debacle.

Fiorina, too, is impressively talented. Her resume is eye-popping, especially, as far as I’m concerned, her decision to study philosophy and medieval history at Stanford, but her touted rise from secretary to CEO is a bit of fable. She is, in fact, the daughter of a federal judge who had been the dean of the Duke Law School. We all have to start somewhere and so Fiorina passed through the steno pool or something like that — clearly on the way to something and somewhere else. She always knew the fork goes on the left.

We live in an age of false political messiahs who emerge out of some mist and capture the fervid attention of cable TV anchors — and then, as day follows night, the public. In the last election, we had the delusional Michele Bachmann for a frightening moment, and then Sarah Palin, heroically uneducable, and then the nine-nine-nine guy whose name, I confess, I forgot. (I just looked it up: Herman Cain.)

This time the political messiahs are Donald Trump and Ben Carson — one, two in most polls at the moment — neither of whom is qualified to hold political office. Carson reminds me more and more of Chauncey Gardiner, the implacably innocent character played by Peter Sellers in the 1979 movie “Being There.” As for Trump, he is the star of his own newsreel, a preening Mussolini manque whose poll numbers are already falling. He will not be renewed.

Now it is Fiorina who is moving up. She performed swimmingly at the recent Republican debates, the political equivalent of Depression-era dance marathons (I was waiting for someone to drop), emitting perfectly formed sound bites, some of them even true and one of them even telling: “Name an accomplishment of Mrs. Clinton’s.” (Give me a minute.) But all she had going for her is that she was once the CEO of Hewlett-Packard. During her tenure, the stock plummeted 55 percent, and while some of that could be attributed to hard times in Silicon Valley, the board of directors did not agree. They fired her.

Here we have the salient fact. Fiorina tries to make the case that she was a whiz of a corporate chief and she has, of course, her own set of numbers to try to prove the point — including that doubling of revenues. (Yes, by buying Compaq.) What matters most, though, is that she could not get along with her own board. It canned her — and the vote was not close. No one supported her.

Now, that says something. It says that she lacks the one quality most essential in a politician, especially a president — the ability to persuade others, especially your opponents, to go along. For much of his presidency, President Obama has lacked that ability — or failed to exercise it. Washington would be a fetid and poisonous place anyway, but Obama has not made it any better. Congress has not been his pal — and that includes Democrats.

Good ol’ Hoover was one hell of a businessman. He was brilliant, but unapproachable. He was a genius organizer, but a political klutz. He proved that being brilliant in business can make you rich, but not a great or even a good president.

Fiorina is similarly skilled, a sharp mind, sharper elbows. She, too, amassed a fortune in business. (Her $40 million golden parachute helped.) But she has never held political office, so we can only guess about her leadership abilities — whether she is persuasive, as opposed to dictatorial — but we do know that she got fired from the top nonpolitical office she held. No other company hired her. Why should we?

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