Every serious defence analyst has laughed at the idea that the F-35 has a secret killswitch. This would be the dumbest thing ever to include in an aircraft, because there is always the possibility that your enemies could find out about it.

just cryptographically sign the kill switch transmission. the fighter would contain the public key to verify, but enemies would need the private key to trigger it, which the NSA would keep buried in cold storage like the DUAL-EC-DRBG trapdoor key.

you'd probably also want to include the fighter's serial number or IFF transponder code, so the enemy couldn't capture or replay.

Consider; if an F-35 kill switch did exist, any buyer of the craft could invest the resources required to go over every inch of circuit and line of code and find it, and then deactivate every US F-35.

there's something like 100M LoC of C++ (not Ada 😥) in an F-35. and Canada doesn't have the sources, so they'd have to decompile that. maybe they could focus on the radios, radar and other devices direct connection to receivers, but the implant might be downstream, and there's a lot of ways to hide an antenna.

even dumping the chips isn't easy. many of them likely have security features, since they contain classified algorithms which the DoD would rather enemies not be able to extract from the downed wreckage of a fighter. certainly the JTAG pins are not going to be enabled. even die shots could be frustrated by metal meshes over the wafer or possibly even microscopic amounts of explosives triggered by de-lidding.

But this "killswitch" nonsense just derails that important discussion into paranoid conspiracy theorist nonsense rooted in the deranged ramblings of a self-aggrandizing madman.

there's secure ways to build a kill switch, there's an abundance of places to hide it in a highly complex fighter, and this kind of spooky stuff is well within the NSA's wheelhouse. it's the kind of thing NSA is known for, even - the Crypto AG CIA front, the DUAL-EC-DRBG backdoor, TAO's clandestine program to intercept and backdoor mailed routers and servers. they clearly can do this kind of thing, since they clearly have before.

did they backdoor the F-35? I don't know, but it's plausible, and CSIS/CSE should investigate.