Spare parts and training are not enough to maintain a fleet of fighter jets. You need experienced in-house technicians to provide the maintenance and replace th

Spare parts and training are not enough to maintain a fleet of fighter jets. You need experienced in-house technicians to provide the maintenance and replace the black-box electronics, which means you're still at the mercy of whatever country manufactures the jets. Doesn't matter if it's China or the US, if they decide a year down the line that they don't like you, guess what? No servicing for you, and your fleet of fancy jets will only last until they break down, or get remotely disabled/bricked/self-destructed with a kill switch. Maintaining a Sovereign Nation 101 is that you do not entrust your national security to another country. Sure, it's more expensive to do your own R&D and manufacturing, but you get the peace of mind that your continued existence does not depend on a foreign government's continual blessing.