For an organisation that talks a lot about peace, the International Olympic Committee seems to be quite partial to the occasional outbreak of violence.
Back in the day, an Olympic truce was a sacred tradition that could last for months. Athletes and spectators would be able to travel to the Games without fear of attack. Wars were halted, legal disputes postponed and death penalties forbidden.
The Olympics were about as safe as it got in ancient Greece, which causes one to wonder what they would have made of London 2012's BMX competition.
Thursday's quarter-finals in the men's event included 10 crashes in 20 races, involving 21 riders, two of whom had to withdraw injured.
"It would have been nice to have qualified in three rounds," explained a surprisingly relaxed Khalen Young, who was forced to ride two more rounds before booking his place in the last 16.
"But in the first round a sniper shot me in the back, and I went from first to last.
"It just blew my hand off and I went over the bars.
"So I just went back, got the doctor to work on me, and scraped together a couple more races.
"It would be nice to be pain-free for the semis but that's part and parcel of BMX."
The Australian was joking, of course, there was no sniper and his hand was not blown off. But Ecuador's Emilio Andres Falla Buchely did clatter into his back wheel and send him face first into the tarmac at about 25mph.
British hope Liam Phillips was in the next race, and his arrival at the start elicited the first big roar from the 6,000-strong crowd.
Hopes of another chapter in the GB cycling success story were reasonably high, providing Phillips could pick his way around the bumps, jumps and hairpins on the 440m course, something that Falla Buchely and Young had demonstrated was easier said than done.
Not that anybody needed to tell Phillips that. Three months ago, at the World Championships in Birmingham, the 23-year-old from Somerset was also shot by a sniper and ended up with a broken collarbone.
The day before, he had won a silver medal in the individual time-trial competition. Suddenly, he was a doubt for his home Olympics.
But, as Young's answer to his health issues would imply, BMX riders don't mind a little bit of wear and tear. "That's BMX," goes the refrain.
So there he was, wheel resting against the automatic gate, looking down a steep eight-metre slope, with seven rivals for close company. Did he flinch? Don't be silly.
"I've been on the receiving end of a lot of crashes but you block it out," Phillips said after sailing through to the semis on the back of three second-place finishes.
"But you know that many people in the crowd want to see a crash - it's a bit strange, but it's exciting."
Athletes are not expected to so accurately identify a flaw in the human condition in post-race interviews, but an explanation of what Phillips was referring to came in the very next race.
New Zealand's Marc Willers won the all-important dash to the first corner and therefore missed the highlight of the day for the vast majority of the audience: David Herman taking out France's Joris Daudet, and everybody else too.
"There are bikes all over the place," screamed the announcer. "It's a yard sale, ladies and gentlemen!"
Willers coasted to the line, while those who could, jumped back on and scrambled for the minor places.
"Everybody is hungry at the Olympics and some are ready for anything," said a phlegmatic Daudet.
"I don't think we had too many crashes today, it's normal that we rub on each other a little."
Daudet's last sentiment may have been a little mangled in translation but the riders accept the risks because they love what they do.
Yes, BMX racing is a tad dangerous. And yes, if you fall off you will feel it for a while afterwards. But it is also undeniably athletic, great entertainment and very skilful.
Jamie Staff won an Olympic gold medal and three world titles as a sprinter in the velodrome. He was the best in the world at the first lap of the team sprint: an explosion of power from a standing start that catapults your two team-mates towards the finish line.
But what is sometimes forgotten is that Staff was a world champion BMX rider, who rode professionally in the United States for years before he decided he wanted an Olympic medal so badly he would have to try boring old track cycling.
"BMX is a great foundation. If you can ride a BMX, you can ride anything," said Staff.
"But it's a bit like gymnastics, you have to start it young. It is very easy for a good BMX rider to become a track rider or even a road rider, but not the other way around."
And looking at the physical challenge of the event, you can see why.
With only 20-inch wheels beneath them, the riders turn their legs over at 180 revolutions per minute.
But they also need strong upper bodies to generate power through the corners and absorb the shocks of the bumps. In many ways, they look like more complete athletes than other riders.
There is also another, more fundamental, reason why the IOC decided this renegade, 1970s off-shoot of classic bicycling was worth a place at the party in Beijing: it is more accessible than other cycling disciplines and therefore more popular with youngsters.
Britain's track stars were riding bikes that cost £20,000, and Bradley Wiggins's road bike is worth at least half that. Phillips and Shanaze Reade, the great British hope in the women's competition, are on machines that cost a few hundred pounds.
So while there are elements of this sport that might still jar with the traditionalists, if the modern Olympics are to remain that way then this is the future.
Even the ancient Greeks would recognise that.