In 21st century and with so many checks on Pakistan by the United States, kill switch on american gear is highly likely. There are 100s of Integrated circuits, and sophisticated instruments inside it, Pakistan is not allowed to do anything to it. How easy is to fail one of the critical systems you won't be able to trace it or even put a blame.
BTW, Pakistani F-16s are 24/7 under American observation. These jets are huge question mark on Pakistan's sovereignty. JF-17 even if less powerful is million times better for Pakistan and its future as we have liberty to do anything to it and use it anyway we want. We can make much improved future variants and our future is linked with its future variants and J-10Cs.
Pakistan as a nation needs to learn that Freedom is most important. A piece of foreign equipment that restricts you and puts checks on you is not worth it.
here's a link for more info how badly Paf F-16s are under american eyes:
In its ties with Turkey, the United States finds itself in a classic Catch-22. Turkish foreign policy often runs afoul of U.S. interests. However, Ankara
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