Vessels in the Taiwan Straits, July 20, 2017. /CGTN Photo

Taiwan's psychological defenses have been breached after the Chinese Foreign Ministry said the so-called "median line" of the Taiwan Straits is non-existent, Chinese mainland observers said on Wednesday, warning that a military conflict is inevitable if Taiwan secessionists insist on that line.

Ministry spokesperson Wang Wenbin made the remarks on Monday, following Chinese air force exercises in the Taiwan Straits on Friday and Saturday, in response to the visit of US Undersecretary of State Keith Krach to the island of Taiwan between September 17 and 19.

Taiwan regional leader Tsai Ing-wen visited the military base at Penghu on Tuesday and tried to motivate the Taiwan air force. "As an air force, how can you let others strut at our own 'airspace？'" said Tsai. 

Tsai's visit also comes amid an undesirable result from Taiwan's annual Han Kuang Exercise, five-day military drill seen as to test Taiwan's ability to resist a PLA attack. The result shows that Taiwan will be short of precision missiles in the war, and finally lose, Taiwan media reported.  

Analysts said Tsai's strong rhetoric reflects the weakness of the Taiwan authority, as Taiwan's military authority recently redefined the military rules of engagement from "first strike" to "the right to self-defense and to counterattack," which means troops will only fire in a clear attack.

The "median line" of the Taiwan Straits is the unilateral and shameless assumption from the separatist Democratic Progressive Party (DPP) authorities on the island, which is also a part of constructing Taiwan secessionism, Zhu Songling, a professor at the Institute of Taiwan Studies of Beijing Union University, said.

Even Joseph Wu, head of Taiwan's "foreign affairs authority," admitted on Tuesday that the "median line" was conceived by the authority on the island despite reacting against the mainland's comment on "median line", zaobao.com reported.  

The "median line" is just a "hypothetical line of non-aggression" drawn by the US during the Cold War. Taiwan authorities then signed the so-called "US-Taiwan Defense Treaty." The US military in 1954 required all Taiwan aircraft and ships to operate in the east of the "median line;" otherwise, they would not be guaranteed by the US military.  Since then, Taiwan's air force has charted its own "air defense identification zone" with the "median line."

The bogus "median line" is only a tacit understanding when cross-Straits relations were eased, and when Taiwan adhered to the one-China principle, Zhu said. 

The "constitutions" of both sides of the Straits support one China, and it is understandable for the PLA to fly over its own country and operate within its sovereign territory, Zhu said. 

The Chinese Navy's first Type 075 amphibious assault ship successfully completed its first sea trial, China's Ministry of National Defense announced in late August, saying the ship has strong capabilities in amphibious combat, and in carrying out a range of tasks.

Wang Jianmin, a Taiwan-affairs expert at the Chinese Academy of Social Sciences, told the Global Times that the Chinese mainland never recognizes the "median line," which is an equivalent to a line that marks the division of a country.

Amid rampant Taiwan secessionism, the mainland's reiteration of its stand on the "median line" is a declaration of China's sovereignty and territorial integrity, said Wang Jianmin, noting the move is a deterrent to Taiwan's DPP authority.

If the DPP continues to test the red line, military conflict cannot be ruled out, as the mainland will assert its sovereignty militarily, Wang said. 

Most Taiwan residents have never experienced the war and cannot understand its cruelty. The thought that "the mainland would dare not achieve reunification by force" will lead to disaster, Zhu said.