> Because US recognize both mainland China and Taiwan as one 'China', without specifying which. The internet would like to tell you that China and Taiwan are totally different country but US policy doesn't recognize that.
US policy does de facto recognizes Taiwan. For instance, it has an embassy there, it just doesn't call it one; and it sells Taiwan weapons over PRC objections.
The only reason the US doesn't recognize Taiwan de jure is a Cold War era compromise with PRC diplomatic policy, and the fact that the current ambiguity works reasonably well for all parties right now. IIRC, some US political factions advocate for formally recognizing Taiwan (for example: https://twitter.com/ambjohnbolton/status/1250501579070980099).
US policy does de facto recognizes Taiwan. For instance, it has an embassy there, it just doesn't call it one; and it sells Taiwan weapons over PRC objections.
The only reason the US doesn't recognize Taiwan de jure is a Cold War era compromise with PRC diplomatic policy, and the fact that the current ambiguity works reasonably well for all parties right now. IIRC, some US political factions advocate for formally recognizing Taiwan (for example: https://twitter.com/ambjohnbolton/status/1250501579070980099).