I am traveling, so can only check-in occasionally. I was starting to compose a reply, and you already got the major points.

Tpp had major problems, IMHO. But just walking away created a leadership void that China tried to fill. It gave China an opportunity, and they are now in a better position in the region because of it. Add one of the articles said, some smaller nations are worried now that we aren't reliable, and are now open to making friends with the local bully ("better to be at Satan's side than in his path").

I can't say whether China was emboldened by this, but they have become more bellicose and belligerent since then. Fortunately, we have a POTUS that will stand by the treaty of 1951. I do expect some shooting battles in the near future.

I'll provide a few more links without excerpting.

asia.nikkei.com - By abandoning Asia s multilateral organizations US empowers China

economist.com - How donald trump damaged americas interests in asia

japantimes.co.jp - China tpp application