When Donald Trump announced he was running for president, I wrote that his chances merited taking seriously. I can’t claim I was alone, but there were plenty who said the idea of the brash property developer becoming Potus was ludicrous.

I’d followed his career, though, and saw a shameless ability to self-promote coupled with a knack of bouncing back from failure. Those, plus a large but lacklustre field of Republican candidates coupled with popular disillusion towards the political Establishment (and nobody typified that class more than Hillary Clinton), augured well for The Donald.

If I’d read Rick Reilly’s new book Commander in Cheat (Headline), I would have been more certain that Trump could reach the White House.

Reilly’s marvellously entertaining account lays bare how the president compulsively and serially ignores etiquette and rules on the golf course. And not just regarding the playing of the game – anything to do with his favourite sport, one he has turned into a business with the ownership of clubs and resort complexes, is there for the taking.

I’ve played golf ever since I was nine years old. From the outset, the notion of cheating was drilled into me and my pals as anathema. It might be tempting, to drop a ball out of a pocket on to a favourable lie while looking for a wayward shot, or to record a four on a hole rather than a five, or to cough loudly just as your opponent swings, but don’t go there. Don’t even think about it.

These, though, and much more are standard tactics in the Trump armoury. He hits a drive into a lake, everyone sees the ripples, but the ball then turns up on the side of the water – with him claiming the “tide” enabled him to find it. On every hole, he tees off first, regardless – thus flouting the convention that whoever wins the previous hole has the “honour” of leading on the next tee.

Not only that, he does not wait for his companions to then hit, but gets into his buggy and races off, down the fairway. On one occasion, recounts Reilly, the Commander-in-Chief was playing a hole where the drive was “blind”, over a slope. He sliced his shot, presumably into the bushes on the right; the second player to go smacked a beautiful drive straight down the middle. When the rest of the party mounted the crest of the hill they saw Trump on the green ahead, putting out for what he claimed was a “birdie”. The second player’s ball was nowhere to be seen. Trump had played his smartly struck ball as if it was his.

Trump maintains he has won club championships at 18 separate clubs – an assertion he made repeatedly in the election campaign. It is some feat, probably not accomplished by anyone ever, not even by the greats like Jack Nicklaus and Tiger Woods. Yet, Trump insisted on repeating it, at rallies, and in interviews.

Closer examination reveals the “championships” were at the the clubs he owned. As proprietor he got to play first, and therefore would always hold the best score for the course, even for a short while. That gave him the right, as he saw it, to boast of being “champion”.

On the business side, he would make outlandish statements about his courses being among the very best in the US and indeed, the world. They were nothing of the sort, but that never stopped him. Enough golfers believed him, and were prepared to pay accordingly to play them – and that was what mattered.

In all he did, Trump had to win, and that meant at playing golf and in business. How he got there did not bother him. He had to come top, or at least convince enough people that he was top. If that means telling lies about his score, the “Trump Bump”, or crowing he’s won a competition when he wasn’t on the course that day, or being 50 yards from the hole and picking up his ball because he would have holed it, so what? He will do anything to secure acclaim, and fortune.

If he plays for money, it’s not the bet that bothers him. Often, he will not claim his prize. What’s important is the act of coming first – everything after that, including picking up a few dollars, is incidental.

He does not just bend the rules, and shoves good manners on one side. He displays contempt for them, as if they are there to be trashed. Tellingly, he expresses amazement that others do not do the same.

As a passionate devotee, Reilly is outraged. Morally so, because as he points out, you don’t cheat at golf. Other sports maybe, but not golf.

For Reilly, this consistently awful behaviour brings into sharp relief Trump’s suitability for the highest office. That may be so, but it also highlights something else: that Trump gets away with it. That does not make it right, but Trump bends, and pushes and stretches, and not enough people say anything. Effectively, he’s allowed to do what he wants. And he triumphs.

It’s how he emerged victorious, at golf, and in commerce. It’s how he became president.

If you don’t try, you won’t succeed. No one illustrates the truth of that adage more than Donald J Trump, outrageous cheat, and 45th President of the United States.

Chris Blackhurst is a former editor of The Independent, and director of C|T|F Partners, the campaigns, strategic, crisis and reputational, communications advisory firm