 At the beginning of the 1950s, while the Tatmadaw was able to reassert its control over most part of the country, Kuomintang (KMT) troops under General Li Mi, with support from the United States, invaded Burma and used the country's frontier as a springboard for attack against the People's Republic of China, which in turn became the external threat to state security and sovereignty of Burma.The first phase of the doctrine was tested for the first time in Operation "Naga Naing" in February 1953 against invading KMT forces.The doctrine did not take into account logistic and political support for KMT from the United States and as a result it failed to deliver its objectives and ended in a humiliating defeat for the Tatmadaw.