Ominously, Beijing described the violent weekend demonstrations as "deranged" acts that are "the first signs of terrorism," and vowed a merciless crackdown on the perpetrators.

China is being pushed toward a decision it does not want to make: to use military force, as in Tiananmen Square 30 years ago, to crush the uprising. For that would reveal the character of President Xi Jinping's Communist dictatorship, as well as Beijing's long-term plans for this semi-autonomous city of almost 7.5 million.

Yet this is not the only internal or border concern of Xi's regime.

Millions of Muslim Uighurs in China's west are in concentration camps undergoing "re-education" to change their way of thinking on loyalty, secession and the creation of a new East Turkestan.

In June, a Chinese vessel rammed and sank a Philippine fishing boat, leaving its 22 crewmen to drown. The fishermen were rescued by a Vietnamese boat.

President Rodrigo Duterte's reluctance to resist China's fortification in the South China Sea of the rocks and reefs Manila claims are within its own territorial waters has turned Philippine nationalism anti-China.