Audiences will let a politician know when he misses the mark

"You Hollywood guys are all alike," a prominent American politician once growled at me. "You think all politicians are just actors."

Which isn't exactly true. I don't think all politicians are actors. Just the successful ones.

During his presidency, Ronald Reagan always cheerfully acknowledged that his training as an actor helped him politically. The opposition snickered, of course, but he was right: Reagan was a fearless speaker and an off-the-cuff joker, but more importantly (and rare for a politician) he knew how to seem normal, like a regular guy.

The trick to American political success is fairly straightforward: you just have to appear to be more human and lifelike than your opponent. Because most politicians inevitably appear to be pre-programmed, terrified automatons, this isn't such a major challenge. One of the reasons Reagan handily won two presidential elections was that unlike his opponents, he knew how to act like a human being. He beat Jimmy Carter and Walter Mondale because, among other things, he just seemed more real.

Years ago, as a young television writer, I inveigled an invitation to meet the former president in his Los Angeles office. He had been out of office for a few years by then, and was just beginning to show the signs of Alzheimer's, so it was a fast in-and-out, standard photo-op affair (elevator up, smile, hello, handshake, flashbulb, elevator down) but a thrill nonetheless. About a week later, his office sent two copies of the autographed photo, along with the negatives.

He looks great; I look like a doofus intern. He's wearing a professional actor's genial smile and physical self-confidence. I'm off-kilter and grinning like a monkey.

Along with the two photographs, his office mistakenly included in the envelope the negatives to about ten other photo-ops (it had been a busy day, I guess) which, when I held them to the light, showed ten civilians in various poses equally bad as mine, with crooked smiles and awkward postures, looking uncomfortable and out of place. Reagan, though, was in the same position in each photograph.

Ronald Reagan, movie star and president, knew how to hit his mark.

The floor of any movie set is marked with bits of coloured tape. These are called the actors' "marks", and in order for the camera to be focused properly, it is imperative that the actor stand right on top of the piece of tape. It's called "hitting the mark", and an actor who hits his mark saves everyone a lot of time and money.

You see, the "let's pretend" part of acting is easy: look sad when you're supposed to be sad, act scared when you're supposed to be scared. The hard part is to do all that and somehow stand on the tiny piece of tape right when you're supposed to. Without looking down.

An actor who hits his mark every time makes it look easy. A great actor makes it not only seem effortless, but completely spontaneous, as if the floor wasn't covered in little bits of tape. And crucially, an actor who hits his mark is always in focus.

In politics as in show business, hitting the mark – standing under the right light, in front of the right lens, a picture of confidence and grace – is the keystone to a great performance. Reagan – and, to a lesser degree, Bill Clinton after him – knew that the theatre of the presidency is pretty much all there is to it.

As far as national powers are concerned, the US president can fire missiles and print money. For everything else, he's got to use charm, wiles, and a certain amount of fast-talking salesmanship.

Last week, faced with an angry and fractious population, President Barack Obama missed his mark. By a wide margin. The voters delivered a decisive and undeniable drubbing, and they left a president who only two years ago was soaring along with stratospheric approval ratings looking baffled and nonplussed. The formerly invincible Mr Obama, movie star cool, with an aloof and above-it-all charisma, looked in post-election interviews like an amateur searching the floor for his mark. Out of step and out of focus is an awfully tough place to come back from.

Just as the audience wants a great show, the voters want a successful president. Nobody wants to sit in a dark theatre and watch the star fumble around for his lines. But patience is not a plentiful virtue in audiences or voters, so Mr Obama, star of the currently troubled television series entitled "The Presidency of Barack Obama", had better find his mark fast and take back the stage, because this audience is not afraid of a little recasting.

Rob Long is a writer and producer based in Hollywood