TEI is a good subcontractor for engine parts. There is no doubt here. However, the problem here is GE F110 (and F404 for that matter) is intellectual property of United States of America and THEY have a final say over those engines, NOT TEI. There is no point of being upset with me for saying the truth.
And I don't think you are naive enough to actually believe that a "subcontractor" would actually threaten the US of not fulfilling existing contracts nor receiving new ones from major companies (the EXACT reason why F-35 supply chain keeps Turkish companies around unilt the existing contracts expire) just because the US refuses to hand over invaluable US gasturbine engines and it works out in favor of Turkey at the end. No amount of lobbists will do any good. It is about national security and even the America's 'greatest ally' Israel couldn't get away with it despite of all business ties & money & influence that they have with USA.
The US refused to do with LHTEC engine
and It is highly likely to happen again with GE F110 & F404.
Unless, of course, Turkey has some dirt on Biden.
I don't think the S400 really think that if national security is threatened, but can not accept the problem of supply and more expensive because the product can't come from Turkey. F35 massive project and wasted a lot of money. When it comes to security, compromises mean nothing compared to the money spent on the F35. So remove those problems instead of Turkey could see the same response even England. F110 or F404 is not really that important, old and commercially it will no longer make sense. Put aside production, I don't even think GE would care if we copy it.