

From a game-theory standpoint (which markets are an instance of such a game) he is not even incorrect. If we tax someone at 15%, while the US doesn’t they will take their business there (if possible). This is not a normative statement, this sucks and will lead to the world’s destruction (literally wiht global warming, and the same for arms races and war). But is is correct.
Here is my (semi) hot take: To really change anything in the world you cannot be game-theoretically naive. We cannot just by cynnical like the market-liberals, because they are willing to sacrifice the planet and humans for their goals.
We need to be post-cynical. Recognising that just claiming the morally right thing will never get us the power to change anything and just striving for the power to change will make us just as evil as them. If we want to change things for the better we have to hold them both in mind.
They never intended to follow through, or do it so anyone can easily defect the agreement.
The US has real power. Economically and military power. There is a reason they published their plans to invade the Hague should any American be convicted at the ICC. Some similar arrangement would be found with this.
You have to think as cynically as possible, the people in power will too. Then think of something that all sides avoid that thing or you will be thrown under the bus by however holds power.