TAIPEI — After soaring to power last year, President Tsai Ing-wen — arguably the most powerful woman in the Chinese-speaking world — now finds herself on the political hot seat following the arrest in China last month of a Taiwanese human rights activist.

Lee Ming-che, an NGO worker and affiliate of Tsai Ing-wen's Democratic Progressive Party (DDP), hasn't been heard from since March 19. Beijing says he is being held on "suspicion of endangering national security," but has otherwise offered little information about Ming-che's detention.

In Taiwan, all eyes are on Ing-wen, who was elected in a landslide in January 2016 and took office in May. So far she has been notably restrained and low-key in her dealings with mainland China, especially as compared to former president Chen Shui-bian (2000-2008), the last DPP member to lead the country. It appears that Ing-wen wants to avoid earning the kind of "troublemaker" label that China attached to Shui-bian. But in Taiwan, her approach is attracting criticism, particularly in light of the Ming-che situation.

"If the case is left to drift without concrete action, how can the Taiwanese people trust that this government is capable of protecting its citizens and handling cross-straits affairs?" said Yu Mei-mei, a well-known commentator. Another high-profile pundit, talk-show journalist Hu Zhong-xin, accused the president of behaving like a "soft-footed shrimp."

Complicating matters even more are developments involving Ming-che's wife, Lee Ching-yu, who tried to fly to Beijing to speak with Chinese authorities directly only to discover, at the last minute, that her visa had been revoked. "If I do not stand up to fight against such injustice, Taiwan will always be a victim," she told reporters.

The pro-China Kuomintang Party suggested to Ching-yu that she be more discreet in her approach to the issue. The detainee's wife balked at the idea. "If we have freedom but no dignity, then we're no better off than dogs," she said. Such language only raises the pressure on a new president facing an old problem.

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