BEIJING — Warning that protests convulsing Hong Kong were crossing a line, China hinted broadly on Wednesday that it was prepared to use military force in the territory if necessary to retain Beijing’s control.

“The behavior of some radical protesters challenges the central government’s authority, touching on the bottom line principle of ‘one country, two systems,’” said the chief spokesman for the Ministry of National Defense, Senior Col. Wu Qian. “That absolutely cannot be tolerated.”

It was both the most explicit warning to date since protests began in the former British colony and a stark reminder of who has ultimate control over Hong Kong’s fate.

Colonel Wu made the comments at a briefing in Beijing on a government document outlining China’s defense strategy. Citing protests on Sunday outside the central government’s liaison office in Hong Kong, which protesters splattered with paint and defaced with graffiti, he made clear that the vandalism was straining Beijing’s patience.

China’s state television, which had largely ignored the protests, highlighted the damage at the liaison office, calling it “a humiliation of our country’s dignity.”

Responding to a question, Colonel Wu pointedly cited the specific article of a law detailing relations between Hong Kong and the People’s Liberation Army. It allows the military to intervene, when requested by Hong Kong’s leaders, to maintain order or assist in cases of natural disasters.

The People’s Liberation Army has for years maintained a garrison of 6,000 soldiers in several bases around Hong Kong. But China has never before ordered them to intervene in the territory’s affairs, though several hundred did help clear trees and other debris after Typhoon Mangkhut battered the city in 2018.

The new defense strategy unveiled in the document did not mention Hong Kong, but it identified efforts to divide Chinese territory as the country’s most pressing security threat.

More at https://www.nytimes.com/2019/07/24/world/asia/china-military-hong-kong-taiwan-protests.html