The period when Chiang Ching-kuo served as Premier of the ROC largely overlapped the process of normalization of US-PRC relations. How did the ROC government, which in effect relied on the US to defend “Taiwan” by the Mutual Defense Treaty signed in 1954, attempt to survive the security crisis of de-recognition from the US with the termination of the treaty? Meanwhile, the ROC government, which was leaving the UN and losing support from the international community, had maintained the “Unity of Offensive and Defensive” strategy. How did the ROC government consider about “Retaking the Mainland,” which aimed to restore lost land, as the legitimate China?

The leaders of the ROC government and the military were deeply concerned about the trend of US-PRC normalization negotiations and aware of the day to come in the near future. However, hey hardly envisioned a situation in which the ROC would defend “Taiwan” independently after the “Expected de-recognition from the US.” Behind this was estimation of the PLA’s forces remaining at the stage of preventing “Retaking the Mainland.” (from the ROC military). Namely, the leaders of the ROC did not feel anxiety about “Defending Taiwan” on their own because there was no immediate danger in preparation for the PLA’s invasion of Taiwan.

The ROC military officers had the realistic belief that conducting “Retaking the Mainland” was difficult, but they also strongly felt that it was their responsibility to accomplish the mission. Nonetheless, meanwhile, “Retaking the Mainland” was essentially the task of some special operations forces. Above all, the ROC government as a whole lacked awareness of achieving “Retaking the Mainland.” For this reason, even if the power struggle that unfolded after Mao’s death was considered a chance for counterattack, it was not possible to complete such task.

Premier Chiang Ching-kuo had limitations in leading national defense development. He had virtually full control of the military shortly before taking office as premier, but he was on behalf of the President during Chiang Kai-shek’s life. Until then, he was assumed to have taken leadership in national defense development, as well as political reform and economic construction. Yet, those were to continue the orthodox of the emphasis of “Retaking the Mainland.” Shortly after Chiang Kai-shek’s death, Chiang Ching-kuo showed his vision for military reform, but it was implemented specifically only after he became the President in 1978 and seized control of the military’s supreme power, both in name and in reality.

1979年1月の米華断交後，米国が台湾関係法を制定したことで，国府は台湾の防衛に関して米国から一応の保障を得ることができた。だが同法は米華相互防衛条約と異なり，米国に台湾防衛の義務がなかった。そのため蔣経国は単独で台湾を防衛することを想定し，「大陸反攻」の態勢を保持していた国軍を「台湾防衛」型の軍隊に改編させた。また，同法に依って提供される「防御性」兵器も米国の判断で選択されるため，国府のニーズに合った兵器とは限らなかった。それゆえ国府は，「大陸反攻」のイデオロギーが色濃く残る大規模な陸軍兵力の削減によって経費を捻出し，兵器の自主開発・生産体制の構築と米国以外からの調達で軍近代化を進めた。米華相互防衛条約の失効という安全保障上最大の危機への対応を迫られた蔣経国は，実質的に「大陸反攻」の構想を「放棄」した。そして国軍は「攻守一体」の軍事戦略に基づく「大陸反攻」任務とのジレンマを抱えつつ，「台湾防衛」のための軍隊へと変貌していくのであった。