The separatists and anti-China subversives in the Hong Kong Special Administrative Region who have been trying to wage a Trojan war against the regional and central governments are now on tenterhooks after Hong Kong and Macao Affairs Office Director Xia Baolong elaborated on the principle of "patriots governing Hong Kong".

Xia's elaboration on Monday, the most comprehensive ever of its kind, made known in no uncertain terms Beijing's determination to implement this principle fully.

"Patriots governing Hong Kong" is part and parcel of the "one country, two systems" principle. As late leader Deng Xiaoping, chief architect of this political innovation, categorically pointed out in June 1984, "patriots must form the main body" of Hong Kong's administrators after the territory's return to China. He made clear that patriots are people who respect their own nation and genuinely support the country resuming the exercise of sovereignty over Hong Kong, and would never do anything to harm the prosperity and stability of Hong Kong.

No one took issue with this requirement, not even the British government that was preparing to hand Hong Kong back to China.

Xia has forced the non-patriotic zealots in Hong Kong to face an unpalatable reality: They have no chance of holding power in the SAR no matter how desperately they try.

Some subversives in Hong Kong have managed to make inroads into the special administrative region's political establishment, including the legislature, even though they have openly revealed themselves to be unpatriotic.

This has been thanks to loopholes in the SAR's election system that exist not by design but simply because the drafters of the Basic Law, the constitutional document that guides the implementation of "one country, two systems", had, excusably, not been able to foresee the complexities of politics in post-handover Hong Kong and thus failed to plug those loopholes.

Enough is enough. The political wrangling that has split Hong Kong society and hindered its socioeconomic development in recent years, the social unrest and violent rampages that upended Hong Kong society in 2019, the ruthless and endless filibustering that have impeded the legislature's work and the seizure of local district councils in November 2019 by members of the opposition camp who openly advocated separatism have forced the SAR and central governments' hands.

Action is to be taken without further delay to plug the loopholes that have allowed subversives to sneak into Hong Kong's governance establishment. It is a long overdue day of reckoning. After all, no functioning state tolerates Trojan horses for long.