Last month, the US published the fine print of a US$686 million upgrade deal for Pakistan’s F-16 fighter jets. The deal is for data link systems, new encryption gear and a refit that keeps the jets flying until 2040. The notice says Pakistan can protect the technology to “substantially the same degree” as the US government. The Pakistan Air Force is also the only declared interested buyer of China’s J-35 stealth fighter, a generational leap in technology. The Chinese jet first flew at the Zhuhai...