It gives the host nation a great opportunity to set its narrative. 

The Atlanta Olympics in 1996 came only 12 years after the previous US-based games but I count its Opening Ceremony as the most memorable, not because of the Ceremony itself but because of one man.

Muhammad Ali was a great one-time Olympian, winning the light heavyweight division at the Rome 1960 Olympics at 18 years of age. He was something special. By 1996, he was known simply as "The Greatest".

He was a three-times world champion boxer but he was so much more because he was also a man of great belief who was prepared to take a stand.

As a 22-year-old, soon after he won his first world heavyweight title against Sonny Liston, he converted to Islam and changed his name. He declared: "I am America. I am the part you won’t recognise, but get used to me. Black, confident, cocky. My name, not yours. My religion, not yours. My goals, my own. Get used to me."

At 24, he became a conscientious objector to the Vietnam War. He said he had no quarrel with the Vietcong. He was convicted, and not able to hold a license to box until the conviction was overturned by the US Supreme Court in 1971. By then he was 28.

If being a confident, good looking, athletic black man was not enough of a target in America in the 1960s, converting to Islam, changing your name and openly opposing the Vietnam War were even less popular positions to take.

But his example inspired many Americans. He was also instrumental in shifting the perception of what made an athlete special. This was the world champion putting everything he had - money, celebrity, ability to get endorsements - on the line for a cause.

Muhammad Ali redefined a great athlete to being more than athletic ability and achievements - in his words, more than the ability to "float like a butterfly and sting like a bee".

It was also about being proud of who you are, standing up for what you believe - even if not popular - and helping people to understand one another. He showed the world the power of sport to bring people together and to change the world. It was another level of leadership.

He made visits to Ghana, Palestine, Kenya, Bangladesh, Sudan, India, Zaire and Israel when it was not fashionable to do so. 

He took part in The Longest Walk to help promote Native American rights. He talked a suicidal man down from a ledge. He visited Saddam Hussein in Iraq to convince him to release US hostages in 1990; Hussein did. 

He was a UN Messenger for Peace in Afghanistan. And he undertook countless works for charity, particularly in support of research and awareness of Parkinson’s Disease with which he was diagnosed in 1984, age 42.

When American swimmer, Janet Evans, ran up the steps and handed the Olympic Torch over in Atlanta for the final time, Muhammad Ali stepped into the light. There was a moment of stunned silence, followed by a roar.

Holding the torch aloft on two separate occasions, he was visibly shaking. Not well enough to take part in the final dress rehearsal the evening before, Ali showed all the courage, strength, deft touch and determination that defined his skills as an athlete. 

As the roar of the crowd grew louder, he held the Torch to the wire that led to the lighting of the Olympic flame. It was electrifying.

And I reckon it was up there as one of his greatest triumphs.