The year 2021 was a year of major shifts in international politics surrounding Taiwan. China's military threats escalated in response to Taiwan's refusal to accept unification. The United States stepped up its support for Taiwan's defense in order to deter China's use of force. Japan, too, began to take precautions against a contingency in the Taiwan Strait. The series of developments surrounding Taiwan seem to have changed the framework of the "1972 arrangement," which had lasted for 50 years. The new framework could be called the "2021 arrangement." With this in mind, the author would like to summarize what has changed in the intervening years and what continued to change in 2021.