This is the national anthem of Taiwan (also known as the Republic of China) and the party anthem of the Kuomintang.
From 1930 to 1949, it also served as the national anthem in mainland China,
being discontinued as per the 1949 establishment of the People's Republic of China.
It became the national anthem in Taiwan in 1945 as a consequence of Taiwan's return to Chinese rule after the surrender of Japan.
The Three Principles of the People referenced in the anthem are nationalism, democracy, and people's welfare.
This ideology was put forth in 1905 by Sun Yat-sen, who served as president of the Republic of China in 1912 and Premier (chairman) of the Kuomintang from 1919 to 1925.
The informants have chosen to remain anonymous,
given that in their homeland,
public criticism of the Chinese Communist Party (the very party that established the People's Republic of China in 1949)
is heavily censored and legally penalized.