While no doubt on the Chinese side its KOOL to talk about "Trump Stunts"? in the rest of the world, everyone realizes that China seizing reefs and shoals and building them up militarily, is the primary provocation in the region,, I believe Mr. Trump stated he didn't blame China?? (he obviously blames Pres Obama) for being weak and allowing that to happen in a vacuum..
So Mr. Trump is responding to that provocation in a strong, but even handed manner, no doubt that almost everyone with a Chinese world view, will seek to blame the US, Japan, Australia, the Phillipines, and Moe, Larry, and Curly!
So China has a desire to ramp up J-20 production, and realizes that they need more capacity than Chengdu is able to generate, so the FC-31 is moved to the front burner!
I'll make another prediction, if the US is unable to normalize relations with Russia?? (the Democrats and never Trumper's have made that damn near impossible), then Russia and China will begin to work together to bring Chinese engine technology up to a much more capable level, in fact that is already going on, and Russia continues to provide much of China's high end military jet propulsion...
In fact if the Chinese and Russians are NOT working together to bring their engine technology up to the Western Standard, they are making a huge mistake.....
In fact, I would say that current engine technology is creeping up to the 5.5 range with dramatic improvments in fuel flows and thermal management.