For decades trusting the US was no problem at all. The relationship was mutually beneficial. Cooperation and trust among nations is possible and Juche (completely self-reliance) is not a worthwhile goal at all. So, sure, cooperation is great and should always be a goal – it also secures peace (people who are economically intertwined are less likely to go to war with each other).

The issue is the US burning up that earned mutual trust. And at some point you have to sadly abandon ship. Cooperation is great, trade is great, but not under all circumstances and all the time.