Nixon acknowledged the "One China" policy, not two, when the US shifted diplomatic support from Taiwan (Republic of China) to mainland China (PRC). Taiwan is n

Nixon acknowledged the "One China" policy, not two, when the US shifted diplomatic support from Taiwan (Republic of China) to mainland China (PRC). Taiwan is not a "major" US ally, rather the US is Taiwan's major ally. The US has several other regional countries it has a significantly greater alliances with, such as Japan, South Korea and Philippines. Though through an act of Congress, the US may (depending on the situation) have some obligations to aid Taiwan in its defense if attacked by mainland China.