In early March, the UN Security Council passed Resolution 2270, sanctioning North Korea, and this resolution is indeed an unusual and remarkable document. This resolution introduced what has been correctly described as the strictest sanctions regime ever, and it was supported not only by the United States, but by all other permanent members of the UN Security Council, including China.

Frankly, this was a surprise to many observers, including yours truly. Shortly before the resolution was passed, in January and early February, I visited both Beijing and Washington and then my impression was that the Chinese – at least, until