Not really mechanical engineering machinery are subjected to high temperature, friction and high centrifugal forces, vibration, fatigue, creep, wear and tear. So it depend on material science, precision machining, skill, design ingenuity , access to precision machinery like CNC. Trial and error over time. Which take a long time to master. No wonder only old tech country like Germany, Japan, US, UK, French are the leader in this field.Seems China's MechE accomplishments trail ChemE and Electric/Electronic Engineering. Lack of consumer goods using MechE perhaps?
Japan does ok with engines. Not stellar but ok. They have a pretty modern regular combustion engine industry. For example they designed and produced the Type 10 tank engine and transmission. With regards to aircraft engines, they made the engines for the Kawasaki P-1, and the IHI XF-9 engine prototype for the F-3. They make their own rocket engines like the LE-5 and LE-9.
They also produce a lot of engines under license or just straight out acquire them but they could be doing worse.
In the civilian sector they produce large gas turbines for power plant applications - among the best in the world.
Offtopic but jumping in to say that Japan is dropping its budget capYep. I think Japan still has an overall better industrial base for engines than China does but its military engine programs are not as well funded and spread out as China's. If Japan didn't have a military budget cap, they would be tier 1 for sure.
“We must increase our defense capabilities at a radically different pace than in the past,” considering China’s increased capabilities,
"We will properly allocate the funding we need to protect our nation" without considering outlays in relation to GDP, he said.
Enjoy your hypothesis, however there is too much bad blood between the two before and after the WWII. Would not see the issues of Taiwan, Diaoyu [spelling] island will be solved in anytime soon as Japs and yanks support each other to frustrate China. Recently, Japs have proposed to have 500 armed soldiers to stay on the island and to defend it. Unless these two allied antagonists face reality that these islands belong to China, there is little hope for peace. Historically and geographically the Diaoyu island chain belongs to China and Taiwan is part of China. Face reality. Period.Yep. Which is why I noted that.
Would be interesting to see how well Japan does in a few decades time as it goes into these military propulsion fields without hands tied. It would be in all east asian nations interest if Japan and China develop a working relation which means lower threat of destabilising forces like war or trade wars, but a friendly Japan China would mean at least resolving island dispute and Korean tensions. If the Korean war was to become officially over and there is reduced threat of war from either side, Japan doesn't need to be a threat to China and vice versa. Although I doubt either side will settle island dispute and concede. Hopefully a mini arms race brings out the best and further boosts China. Japan's economic woes are not exactly on its way to being over yet. It is putting people into poverty while China's still a per capita fraction of Japan's productivity, it still has population advantage (workable and productive population) and it is going to be on an economic upswing for the next 20 years.