TAIPEI, Taiwan — As Taiwanese military experts describe how their forces could punish a Chinese invasion of the island, they might almost be describing D-Day in 1944: amphibious landings, fighter planes dueling for air supremacy, and tank battles for control of the capital.

Chinese claims that they could subdue Taiwan in 100 hours are “impossible” because of the island’s stiff defenses, one expert insists. “If they fail within 100 hours, with great casualties, they might reconsider,” he argues, because of the risk for “internal instability" for President Xi Jinping.

The specter of war across the Taiwan Strait has animated military planners since 1949, when Gen. Chiang Kai-shek fled here with his nationalist army after the Communist Party gained control of mainland China. The Ministry of Defense distributes a book with glossy photos of Taiwan’s defensive weapons and stirring captions: Air force jets are “Eagles that Dominate the Skies;” a navy destroyer is a “Blade the dominates the sea.”

But traditional military combat may be the least of Taiwan’s worries. More immediate, and potentially threatening, is the daily campaign to undermine Taiwan’s democracy and promote fealty to Beijing. This hybrid warfare is cheaper and harder for an open, democratic society such as Taiwan to resist than a conventional military assault. And it’s a challenge that Taiwanese experts are struggling to understand and address.

Taiwan’s self-defense dilemma was discussed in nearly every conversation here this week during a visit by a bipartisan study group organized by the German Marshall Fund, of which I’m a trustee. Polls show that Taiwanese favor the current balance, in which the country maintains its own democracy but doesn’t formally assert independence. Beijing keeps squeezing, in what appears to many Taiwanese to be an effort to make the island a province of China, without using overt force.

“The Taiwanese have faced an immense conventional military threat for decades, yet now they also have to be concerned about Beijing’s increasingly sophisticated efforts to lure their citizens back to ‘mother China.’ It’s a challenge that requires significant coordination across government and civil society, and ultimately can’t be solved by more missiles or jets,” argues Jamie Fly, a former Republican Senate staffer who organized the German Marshall Fund trip.

Here’s how one Taiwanese official explains the subtle Chinese threat, spread through social media, newspapers and television in an influence campaign that touches every business, farm and worker: “If you support the DPP [the ruling Democratic Progressive Party, which favors Taiwanese self-determination], the whole island will be punished. But if you help Beijing, you will benefit.”

Explains another senior official: “To promote peaceful unification, China will try to influence this country so that Taiwan will have a more China-friendly government.” The showdown will come in the 2020 presidential election, which will pit a pro-Beijing party against the DPP.

Ketty Chen, vice president of the Taiwan Foundation for Democracy, explains that every day, pro-Beijing operatives post thousands of pieces of disinformation on Facebook and other social media platforms. For example, a site called “I love to exercise” intersperses fitness tips with propaganda against President Tsai Ing-wen, a DPP-backed lawyer and economist elected in 2016.

“We want a healthy relationship with China, but we don’t want to be ruled by China,” argues Raymond Sung, director of Taiwan Democracy Watch, at a roundtable organized by the Prospect Foundation, a government-backed think tank. A similar desire for self-determination was expressed by a half-dozen students at National Chengchi University. “We’re trying to make a new identity for ourselves on this island,” explained one student. “We’re going through a nation-building process.”

How can the United States help militarily? It’s tricky.

Taiwan wants American weapons and tactical support, but not so directly or visibly that it triggers a Chinese escalation. If the the United States considers a show of force to deter Chinese military action, for example, the Taiwanese believe that a joint effort, conducted with other nations, would be safer than unilateral U.S. action.

The Taiwanese also insist that they wouldn’t need direct U.S. combat support if conflict began; indeed, U.S. intervention might prove counterproductive by drawing a punishing Chinese response.

President Tsai is walking a tightrope as she manages these security issues. Her goal is to preserve the status quo, but I erred in a recent column by implying that she accepts the idea that there is one China and Taiwan is part of it. Instead, Tsai’s aides explain, she wants a continuation of peaceful relations across the strait and a status that’s neither independence nor unification — the same middle ground that polls say is overwhelmingly favored by Taiwanese.

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