Fears that the Republic of China on Taiwan will declare formal independence as a nation separate from Communist China are provoking fresh threats from the mainland along with constant military pressure.

A senior Chinese colonel, Zhao Xiaozhuo, offered that rationale for Chinese forces to invade the island when he called on Chinese state TV for removal of “the tumor” of the Taiwan independence movement with “the scalpel” of a surgeon.

“The core root of the problem is Taiwan independence separatist forces,” Colonel Zhao of the Academy of Military Sciences of the People’s Liberation Army, the name of Communist China’s armed forces, said. For that reason, he said, the PLA has had to stage air and naval exercises around the island.

Those comments indicated that President Xi of China would claim invasion of the island was necessary to stifle plans by Taiwanese leaders to make the island an independent nation. Taiwan has functioned separately from the mainland ever since the anti-communist leader, Generalissimo Chiang Kai-shek, led his Nationalist forces to the island as Mao’s Red Army was taking over the mainland in 1949.

In fact, Taiwan’s president, Tsai Ing-wen, has specifically opposed suggestions that she press for Taiwan’s independence. It’s widely believed that a declaration of independence for Taiwan would provide Beijing with a pretext to try to recover the island.

That view is shared by Taiwan’s vice president, Lai Ching-te, whom the DPP has nominated to run for president next year as Ms. Tsai’s successor. At a press conference early this year he argued “we do not need to further declare Taiwan’s independence,” as Taiwan is already “an independent and sovereign nation.”

Mr. Lai, long reputed to be a strong advocate for Taiwan’s de facto freedom from the mainland, replaced Ms. Tsai as leader of the ruling Democratic Progressive Party after the DPP fared poorly in local elections last year

The DPP faces its most severe threat from the Kuomintang, or Nationalist party, including many adherents and descendants of the mainlanders who fled to Taiwan before the Communist victory in 1949. The man who preceded Ms. Tsai as president, Ma Ying-jeou, leader of the Kuomintang, back from a visit to the mainland, urged reconciliation since “we are all Chinese.”

Ms. Tsai and her government are at odds with the implications of that view. It was “imperative,” Taiwan’s American office said, “that like-minded countries stand together to counter China’s threats.”  Taiwan is counting on America to honor its “commitment” to the island’s defense even though America switched diplomatic recognition to Beijing from Taiwan in 1978.

The Chinese, meanwhile, are keeping up unremitting military pressure. Taiwan’s defense ministry reported that 35 Chinese fighter planes and eight warships had maneuvered just beyond Taiwan waters so far this week. 

Taiwan, vastly outnumbered, sent its own planes and ships to monitor what the mainlanders were doing.