The Big 3 US have been screaming about the ME3 funding the regions airlines.
Very obviously there is a big difference between subsidising an airline and an aircraft manufacturer...
It greatly amuses me that the 100% government run airliner companies in China and Russia are given a complete pass while Boeing, Airbus, BBD and Emb seem to perpetually be in court over government subsidies.
A and B have been locked in a battle for quite awhile over government subsidies.
So war we have no information how money will be giving to COMAC. Don't forget that A, B, E and BBD get money all the time from the governments or states where they have their factories, too. And totally legal. As long as these payments are not pure subsidies, but loans with a favorable, but not market-distorting interest rate, this is an accepted practice to stipulate growth. Many WTO rulings in the infamous A vs B and B vs A cases came exactly to this result. Of course there were also payments on both sides to "help" on company in an unfair way (ultra low interest rates, no interest to pay at all, plain subsidies), but the majority of the WTO rulings got dismissed because A or B just got regular loans from the local governments.
And of course all this mambo-jambo about loans and interest rates totally leaves out all the indirect sponsoring of all four companies by military contracts and funding for research at NASA, DLR and similar state-run organisations who then give their research results to their local aircraft manufacturer. And not forget the help of import-export-banks (on both sides) or just the loans with market-distorting interest rates to 2nd and 3rd world countries who in return place some nice aircraft orders, perhaps including some private 777/A340 for the local dictator/king/MP/whatever.
I'm not a fan at all of these two dictatorship-run countries and how they handle their economies, but at this point we don't even know how money will be allocated and on which conditions, so I would wait before going to court at the WTO (which both countries are taking part in btw).
Far for interesting for me is, how much technology gathered by Chinese and Russian spies is inside this jet. How much A350 and 787 is in this future MOM/small-widebody? I'm very cautious to write off the Chinese too early. Even the Russians have some small success with their SuperJet, one of these Russian death-traps is now flying for Brussels Airlines.