UNCLOS allow “Freedom of Navigation” for innocent passage through straits that is commonly used for transit, even if it is within the territorial waters of on or more nation(s):
Example of such Straits are the Hormuz, Gibraltar, Florida, Bearings Straits and the English Channel.
PRC regards Taiwan Strait as “within it’s waters” since they do NOT regard Taiwan (ROC) as an independent state, but a “renegade province” of China, as do UN and the US (officially).
The US Navy keep on sending warships through Taiwan Strait to “claim their right” and provoke the PRC Government, although there are a perfectly good route through Luzon Strait that is not provoking anybody. (probably shorter, in most cases):
Just a thought experiment:
What if Iran should send their Navy Supply ship through Florida Strait when going to/from Venezuela? (Not the shortest way but to claim their right)
Or the Chinese or Russian Navy steamed through one of the passages between the Aleutian Islands?:
I think the headlines would be a foot high and screaming for action.
Or what do you think??