There are about a dozen nonstop commercial flights every day between the two countries.  Hundreds of billions of dollars are traded between the two countries every single year.  Taiwan has not harmed a single Chinese military soldier or asset in decades, nor has China harmed any of Taiwan's. Although there have been drills.

War may come.  But it won't come suddenly.  All of the things I listed above would have to stop first, one by one.  There would be lots of warning shots and minor incidents first.

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