Taiwan’s strong responses to the ruling of the Permanent Court of Arbitration (PCA) on the South China Sea, similar to China’s, may not be wise from a foreign policy standpoint, but the reaction highlights the undeniable linkage across the Taiwan Strait, a potential breakthrough in the cross-strait relations.

Since its democratization in the early 1990s, the political narrative of Taiwan gradually moved from a “free China” to a de facto state independent from China, despite keeping the same official title, the Republic of China (ROC). Although former President Ma Ying-jeou endeavored to promote cross-strait integration between 2008 and 2016, the subsequent landslide victories of Tsai Ing-wen and her Democratic Progressive Party (DPP), with their pro-independence inclincations, prove that the majority of voters favor the political separation or the so-called status quo. Under this position, Taiwan is supposed to act like an independent country, whether internationally recognized or not, with its own perspective rather than a Chinese one.

However, the South China Sea, one of the Chinese legacies from the ROC regime, saliently works in an opposite way. The ROC’s occupation of Itu Aba was established at the end of World War II, when the ROC government represented China. Right after the occupation, the ROC announced the eleven-dash line encircling the South China Sea, the basis for the nine-dash line later drawn by the subsequent Chinese regime, the People’s Republic of China (PRC). Thus, Itu Aba (or Taiping Island) is more than a remote place under Taipei’s control, but a clear sign of its unsettled relationship with Beijing.