The sudden downfall of a hero, particularly in the circumstances that surround Oscar Pistorius, generates a kind of communal shock mingled with dismay, a dull ash smeared across the shiny sense of life’s possibilities. This much we know: A beautiful, intelligent young woman, Reeva Steenkamp, Pistorius’s girlfriend, died from gunshot wounds at his house.

Pistorius, an exceptional athlete in both Paralympic and Olympic categories, has been arrested and charged with premeditated murder, which he strongly denies. There appears to be no other suspects. Stories have quickly circulated: The public has been reminded of the athlete’s restless insomnia, his fondness for shooting and possession of firearms and his tempestuous relationships with some of his former girlfriends. His remarks about his hair-trigger responses to suspected intruders have been reread in a more ominous light.

A journalist called Michael Sokolove, in an article for the New York Times last year, concluded from spending time with Pistorius that he was “a great deal of fun”, but “more than a little crazy”, and had a temperament hell-bent on risk-taking. All this information was in the public domain before the terrible event last week. In the main, people disregarded it or fitted it into the reassuring template of the young, fit man who worked hard and played hard.

Now, we are piecing these same fragments together to try to make sense of what happened — whatever did happen — and why. Pistorius was an international hero, courteous and articulate in interviews and we prefer our heroes to seem superior in every way. We cling to the unlikely idea that exceptional achievement carries with it the full deck of admirable qualities. There remains much about Pistorius’s achievements to admire: That is why the mass interest in the case is tempered by sadness. He was a truly great athlete, whose state-of-the-art prosthetic legs sparked a heated argument in sport about whether the curved blades, on which he ran, gave him an unfair advantage. Even that row spoke of a kind of glorious transcendence of will, hope and effort over fate. Who would have imagined that a baby boy, whose legs were amputated when he was 11 months old, would ever get himself to a position in which able-bodied Olympic athletes were worried about his “advantage”?

And yet, in recent years, the public has seen the shattering of the reputation of more than one “hero” sportsman, albeit in a less shocking way. Lance Armstrong, the American cyclist who was seven times a winner of the Tour de France and a cancer survivor, has had his professional standing shredded with the confirmation of doping allegations. Tiger Woods, one of the most brilliant golfers of all time, had his “family man” image destroyed by claims of seemingly compulsive extramarital infidelity. Each sportsman’s scandal has in common a private, almost addictive departure from the burden of perfection that an admiring public has placed upon them. Sport, at the very peak of competition, has a similarity to war. The individuals who perform best are those who can maintain lightning-fast reactions under immense pressure. For them, a system flooded with adrenaline makes perfect sense: It’s where they feel at ease. When things go wrong is when such people return to ordinary life and find it flat by comparison. They are plagued by restlessness; they chase the hit of unnecessary risks.

This has long been recognised as a syndrome among soldiers. I think of Robert Blair “Paddy” Mayne, one of the most outstanding soldiers of the Second World War, who acted with legendary and almost insane bravery. Only peacetime defeated him: He was given to fighting and drinking and died aged 40 in a car crash, a few hundred yards from his home in Northern Ireland. Mayne has rightly remained a hero: Any permanent destruction he wrought — aside from that of enemy forces — was to himself, but it is a reminder of the constant truth of the Walt Whitman lines, even in those we regard as exceptional: “Do I contradict myself? Very well then, I contradict myself? (I am large, I contain multitudes)”.

Oscar Pistorius, like his native South Africa, contained multitudes: From the ability to inspire awe to a reported thread of pugnacious unpredictability. South Africa itself, with its undercurrent of violence, might well have placed him on permanent high alert. In the weeks to come, he will face the painful examination and necessary consequences of his actions. But we need to remember that the very qualities we admire in our heroes can be the same ones that trigger destruction. It might be better for everyone if we admitted that earlier.

— The Telegraph Group Limited, London, 2013