Well you’re right its not treason but it is betrayal. The US has pretty much supported Taiwanese independence for my lifetime.
But before we get into the handwringing lets reflect on the fact that China can’t even win a border skirmish with India. Taking Taiwan back by force is not going to be a cakewalk.
No, it hasn't. The U.S. has supported a "one China" policy for decades.
The issue is whether the "one China" is Red China absorbing Taiwan, or Red China adopting a governing model based on Western-friendly Taiwan.