I'm sure many in the USG are shocked, and not because they are used to Canada and the UK playing along, but because they think every country would bend to our will because of the fear of any economic sanctions we would impose. The truth is that the more globalism marches on, the less of a consequence a given country would really feel from the US (or any other government for that matter) imposing economic sanctions. Many countries have increasingly diversified their portfolio of trading partners, making economic soft power increasingly irrelevant for smaller sovereign states.
HK has nothing to fear with regards to economic sanctions. One can be reasonably sure that even under "One country, two systems", China wouldn't take kindly to economic sanctions against HK, and in the end, the US needs China more than China needs the US.
