With due respect to the various rallying, truck-driving and other motor champions about, the big three of world motor-racing have always been the Formula One championship, the Le Mans 24-hour race and Indianapolis.
Of the three, the Formula One world championship - a truly global event - is the most prestigious, which is why, in terms of motor-racing, Dixon still trails New Zealander Denny Hulme, who won the Formula One world title in 1967.
Indianapolis is a landmark event that stops the United States, like the Superbowl, but on a lesser scale.
In recent years, Indianapolis has lost a little of its pull, because of the rise of Nascar racing.
The big sports sedans - Yank Tanks - attract huge crowds and are the glamour motor-racing events in the United States now.
They attract most of the money, crowds and advertisers.
However, Indianapolis is the one open-wheel single-seater race that undeniably remains a major US sports event, and for Dixon to win it was a superb effort which probably ranks alongside Michael Campbell's win in the US Open golf a few years ago.
So which performance would we place higher, taking the chequered flag at Indianapolis or winning an Olympic gold medal? I imagine it depends on the Olympic event in question.
If Nick Willis wins the 1500m in Beijing, reviving memories of Lovelock, Snell and Walker, that might perhaps rank higher even than Dixon's heroics this week.
But would we feel similarly if BMX queen Sarah Walker wins gold? How about Drysdale, or Vili, or Mark Todd, for that matter? That'll be a thorny one for the Halberg Awards judges to debate.
Talking of Dixon, I haven't noticed this week New Zealanders rushing to concede that the Australians have a claim to him, given that he was born in Brisbane.
We're much better at trying to claim the likes of Russell Crowe, Split Enz and Karmichael Hunt than we are at conceding our transtasman neighbours have any sort of ownership of New Zealand successes!I remember Dixon from the early 1990s and have to smile now when I think back to how wrong I was about him.
He began racing karts when he was 10 and I remember a television news clip of him from 1993.
It was quite a story at the time.
He had been granted dispensation to race in a saloon car when aged only 13, the legal driving age being 15, of course.
During a race at Pukekohe, the youngster rolled the car on to its roof and emerged with tears streaming down his face and a pillow strapped to his backside so that he could see over the steering wheel.
Watching that footage I reflected how ridiculous it was, and what indulgent parents he must have.
"He'll never amount to anything," was my abrupt appraisal from afar.
How wrong can you be? Dixon is now a millionaire many times over, having won $NZ3 million just from his Indianapolis heroics.
He has won important championships in New Zealand, Australia and the United States, including the Indy racing league at his first attempt, in 2003.
Will he attempt to build on his Indianapolis triumph by attacking the Formula One championship? It's possible.
He has the name and the stature to at least be given consideration by the big teams.
He actually dabbled with Formula One a few years ago.
BMW gave him a brief trial, and his times were exceptionally promising, so they brought him back for a two-day test a few weeks later.
On that occasion, he did not drive as well, and that was the end of it.
Neither Dixon nor BMW were happy with the test.
With all the money and fame he could ever want, Dixon might well feel he has done enough in his sport.
He sounds very American and is very businesslike and organised these days.
But if he is looking for another challenge, and itching to prove himself at the highest level, then surely the Formula One beckons.
