KEY POINTS:
On a map, the city of Kashgar looks a world away, more than 4000km west of Beijing across China's vast girth.
But yesterday, the oasis city in the fractious region of Xinjiang felt closer than the Great Wall, that enduring monument to China's mighty dynasties which lies inside the Beijing Municipality.
News of the deadly terrorist attack on jogging policemen in Kashgar was a bloody reminder that security remains a pressing concern for the Olympics.
Trudging through Beijing's security checkpoints (operated, it has to be said, far more efficiently than those of Sydney or Athens) it's easy to become blase and cynical as the guards dig through your bag.
Is this just for show? How much is it about control and how much is it about protection?
Kashgar's separatist guerrillas delivered the answer, even though they struck far from the birds nest-like National Stadium.
For those of us in Beijing, the threat has seemed undaunting. Rower Rob Waddell, back for his third Olympics, noted yesterday that the level of security was high, but only on a par with anything he had experienced before.
"You're certainly not going to get anywhere without your accreditation," he said. "It's what you expect and you feel perfectly safe on the course and inside the village."
In the co-host city of Shenyang, though, the men's soccer team feel more oppressed.
Coach Stu Jacobs said yesterday that moving around the city was almost impossible and that the team were virtually confined to the team hotel and the grounds.
"They're very adamant that if you go off-site, someone needs to accompany you," he said. Players are biding their time watching movies downloaded to their i-Pods.
It's understandable things are a little tenser in Shenyang. It's far from the missile and fighter-jet enhanced protective cloak around Beijing and New Zealand's Oly-Whites are due to face host China tomorrow.
Are any of China's domestic enemies determined enough to seek a starring role during these Games? Perhaps that's a thought to ponder in the security checkpoint queue.