China launches 'gray-zone' warfare to subdue Taiwan Taiwan's President Tsai Ing-wen warned this week of "military threats on a daily basis" from "authoritarian forces." She is seen aboard a guided missile frigate in 2018. -Reuters

Months after eliminating a popular challenge to its rule in Hong Kong, China is turning to an even higher-stakes target: self-governing Taiwan. The island has been bracing for conflict with China for decades, and in some respects, that battle has now begun.

It's not the final, titanic clash that Taiwan has long feared, with Chinese troops storming the beaches. Instead, the People's Liberation Army, China's two-million-strong military, has launched a form of "gray zone" warfare. In this irregular type of conflict, which stops short of an actual shooting war, the aim is to subdue the foe through exhaustion.

Beijing is conducting waves of threatening forays from the air while ratcheting up existing pressure tactics to erode Taiwan's will to resist, say current and former senior Taiwanese and U.S. military officers. The flights, they say, complement amphibious landing exercises, naval patrols, cyber attacks and diplomatic isolation. The risk of conflict is now at its highest level in decades.

PLA aircraft are flying menacingly towards airspace around Taiwan almost daily, sometimes launching multiple sorties on the same day. Since mid-September, Chinese warplanes have flown more than 100 of these missions, according to a Reuters compilation of flight data drawn from official statements by Taiwan's Ministry of National Defense. The data shows that in periods when political tension across the Taiwan Strait peaks, China sends more aircraft, including some of its most potent fighters and bombers, reports Reuters.

These encroachment tactics are "super effective," Admiral Lee Hsi-ming, who until last year was the commander of the Taiwanese military, told Reuters in an interview. "You say it's your garden, but it turns out that it is your neighbor who's hanging out in the garden all the time. With that action, they are making a statement that it's their garden - and that garden is one step away from your house."

Under President Xi Jinping, China has accelerated the development of forces the PLA would need one day to conquer the island of 23 million - a mission that is the country's top military priority, according to Chinese and Western analysts. With Hong Kong and the restive regions of Tibet and Xinjiang under ever-tighter control, Taiwan is the last remaining obstacle to the Communist Party's monopoly on power. In a major speech early last year, Xi said that Taiwan, which Beijing regards as a Chinese province, "must be, will be" unified with China. He set no deadline but would not rule out the use of force.

There has been a "clear shift" this year in Beijing's posture, a senior Taiwanese security official responsible for intelligence on China told Reuters. Chinese military and government agencies have switched from decades of "theoretical talk" about taking Taiwan by force to debating and working on plans for possible military action, the official said.

In a speech Tuesday, Taiwanese President Tsai Ing-wen alluded to the shift. The island democracy is under unrelenting pressure from "authoritarian forces," she warned, without going into detail. "Taiwan has been at the receiving end of such military threats on a daily basis."

Admiral Lee, the retired Taiwanese military chief, believes the only thing holding back the PLA from a full assault is that it hasn't yet achieved the overwhelming firepower needed to overrun the island. Even so, China's military build-up over the past 20 years means it is now "far ahead" of Taiwan, he said. "Time is definitely not on Taiwan's side," he said. "It's only a matter of time for them to gather enough strength."

The Chinese government was asked detailed questions for this article, including queries about the gray-zone tactics and its overarching strategy on Taiwan. In a written statement, China's Taiwan Affairs Office said Beijing is committed to "peaceful reunification" with Taiwan, a formulation it has used for decades. It added that "so-called experts' remarks quoted in the story by Reuters are groundless, purely hearsay, and full of prejudice and show a Cold War mentality." It continued: "They even include absurd remarks about the country's central leadership. We are strongly dissatisfied with and firmly opposed to such reports."

Taiwan's defense ministry said in a statement it is stepping up naval and air patrols and improving combat readiness to counter China's gray-zone tactics. The military "sticks to the firm stance of 'not provoking and not being afraid of the enemy,' and the principle of 'the closer they get to the main island, the more active is our response.'"

As the threat mounts, the Taiwanese military is in poor shape to meet it.Interviews with current and former Ta