I suppose I would blame both the United States and the newly ‘recreated’ Taiwanese KMT that claimed their new post-1949 ROC on Taiwan was still the old pre-1949 ROC and still the true China for doing that in that period.
It was thanks to the KMT party-state’s insistence on its orthodoxy that Taiwan missed the chance to declare independence when the PRC’s diplomatic relations were still limited in the window between when it had become undeniable that it would not retake the Mainland and when the PLA could actually do some serious damage to it.