You can't be all things to all people.
You can't do all things at once.
You can't do all things equally well.
You can't do all things better than everyone else.
I'm not certain of the author but the words came back to me after reading this headline, "Technological, Capability Issues Still Plague F-35" on Al Jazeera. The Pentagon has published report that basically says the F-35 is still years from being fully operational. It uses some 8 million lines of code to operate and there are still bugs throughout the software.
The F-35 tried to be everything to everyone (air superiority fighter, air-to-ground attack aircraft, close air support) but it can only do those missions sort of well. Now the USAF has had to postpone its plans to shelve the A-10 until 2022 in no short part because the F-35, which is supposed to replace it, won't be ready until at least then.
Even though the Pentagon realizes the F-35 is the most costly weapon system ever, and one unlikely to provide any kind of return on investment, it still stubbornly sacrifices other weapon systems and personnel to maintain this program. It is nothing short of insanity realized on the backs of the taxpayers.
Sto the F-35 and instead replaced with the newest versions of the F-15E. I don't know if its possible but if they can restart the F-22 production lines, that would be another possibility. While the Pentagon continues to plod along, China bought 24 Su-35 fifth generation fighters from Russia.
China may try to reverse engineer the Su-35 or it may use the aircraft as a way to assess the develop of the J-11 higher. Either way, the Su-35 could replace the F-35 to many countries concerned about its problems. The Su-35 is also likely to see combat sooner than the F-35 meaning it will have more of its bugs worked out before the two fighters ever meet in combat.