It's critical to see the difference between America and the American administration. Under the structure of the US government they are not the same, which is different from how other countries are designed.

American is fairly trustworthy once the whole government is onboard, once something is implemented in treaty. But, without something ilke that, it's only a handshake agreement with once branch, without the whole country involved.

From the Paris accord through the JPCOA other countries seem to miss that.