I'm late returning to this, and I don't normally like whataboutism, and I don't want to be seen to be condoning what is happening in HK, but I have very low expectations for nations keeping commitments made in international politics. I think everyone was pretty clear when the HK deal was struck that it wouldn't make the distance. The UK just wanted to avoid rocking the boat + there was very little that could be done. The US has renagaged on several international agreements in recent history — we all know that these agreements reflect the preferences of those in power at the time and are contingent on it remaining convenient.