There is a way the U.S. could play hardball with Canada, if the Liberal government of Prime Minister Mark Carney decides it wants to limit its purchase of F-35s in favour of the Gripen.
Critics who favour the Lockheed-Martin stealth fighter have long argued that the Swedish-built Gripen would not be interoperable with American aircraft and the North American Aerospace Defence Command (NORAD).
That’s not what you see at the NATO air policing mission in Iceland, where Danish-owned F-35s have been training and operating alongside Swedish JAS-39 Gripens-Cs.
Commanders of both the Swedish and Danish air forces, speaking at the airfield in Keflavik on Tuesday, said the aircraft have been performing well together.


Just means we need more Gripens, it’s not a red card because we don’t want any American tech in our military.
If they go that far, then yes, the only reasonable response would be to stop any purchases of US equipment altogether.
I doubt they will, for that exact reason. It’s the kind of hardball move I’m sure Trump would very much like to pull, but I’m also sure that his handlers / diaper changers recognize how damaging it would be, not just to any future sales to Canada, but future sales across the world. Nobody wants to buy from a store that constantly changes or refuses to honour their own terms of service. There are already concerns that the US might stop offering firmware updates to buyers of the F-35, but those concern are at least hypothetical, currently. If they pull this “red card” it very much stops being hypothetical. Maybe you sell a few more units to buyers who are currently locked in (that might even include Canada), but you lose basically any future business from everyone who has better options.
Even if they don’t go that far, anyone in our history who approved the purchase of equipment from our historically biggest enemy should be in jail.