Let's not beat around the bush. Trump is not very smart, and not at all well-informed. In fact he actively removed anyone from his inner circle who showed signs of being either of those things. So I think China was able to move confidently in a lot of areas, because they knew Trump and his cabinet would fail to understand the significance of their actions. This includes erosion of democratic norms in Hong Kong - Trump doesn't understand or care about democratic values, and has in fact attacked them himself domestically, so that represented a huge opportunity for China.
At the same time, Trump is deeply insecure, and is attached to the idea of military power somehow reflecting his own masculinity. Look at his tweets in response to North Korea's provocations, for instance, and how he made them all about him personally. So I think China was careful not to take action that would cause Trump to feel slighted or emasculated and feel a need for direct military action.
So within that narrow area of military pride and perhaps domestic manufacturing, Trump represented a real threat of retaliation and escalation, but beyond that he was pretty much asleep at the wheel.
At the same time, Trump is deeply insecure, and is attached to the idea of military power somehow reflecting his own masculinity. Look at his tweets in response to North Korea's provocations, for instance, and how he made them all about him personally. So I think China was careful not to take action that would cause Trump to feel slighted or emasculated and feel a need for direct military action.
So within that narrow area of military pride and perhaps domestic manufacturing, Trump represented a real threat of retaliation and escalation, but beyond that he was pretty much asleep at the wheel.