Wow, I could not agree with this opinion piece any more!   I never thought I would read such a great insight from a Canadian Journalist.  Americans seem to be oblivious as to how much damage Trump has inflict to its country and its allies.  

All the things are falling in place for China, thanks to Trump who cluelessly accelerated such power shift by at least a decade.   

Many in South Korea believe that the US is not a reliable ally any more.  They are preparing to survive without the US, which is triggered by Trump. 
Unfortunately, that means South Korea will go back to old (and dark) history of surrendering to China.    So will Vietnam.