While the trade war is real what isn't and has never been taken seriously by the Canadian Govt is the annexation claims. Were that to be the case then military cooperation would have ceased, it most certainly hasn't, and the ordering of new military equipment from the US would have ceased, it most certainly hasn't.
Most of our heavy equipment is located at a few centralised bases. The messaging to the Canadian public has been that our military simulations show our conventional armed forces being wiped out in a few days, and the contingency plans being considered would involve dispersing weapons among the public and engaging in a Guerrilla campaign. Under such a scenario, even if we felt there was a severe threat, then there might be more benefits for maintaining cooperation as the information we'd gain would be more useful than the information they would gain.
I cannot say for certain the view within the Prime Minister's office, or whether the plans to expand military training (etc.) are just for show to a domestic audience.
What I can say definitively is that a lot of Canadians, including a lot of Canadian veterans and service members, take these threats seriously. The mood on the ground is definitely that the threat to sovereignty is greater than the threat of unemployment due to a trade war.
What short strips does the RCAF use for fighter jets in the Canadian North? The answer is none because there are none. From a Billie Flynn blog
here
He also has a second runway myth
here worth reviewing.
Goose Bay is fairly far north. However, to reach the Western Arctic and even parts of the Central Arctic we've needed forward refuelling positions. There are no highways that far north (e.g. due to permafrost), so we're not talking about a Scandinavian approach to dispersal. But we're talking about icy runways, and relatively short strips, in very harsh conditions.
But in acquiring Gripen the RCAF spends more money. The acquisition cost is little different, the operating cost not enough to make up for duplicating all the things needed to support a dual fleet of fighters and the reason the RCAF went to a single fleet with the CF-18 and why the new Canadian fighter capability was also for a single fleet.
True. If we purchased the Gripen, it would make sense to sell the CF-35 portion of the fleet to an allied operator. A dual fleet doesn't make much sense for a country our size.
What technological transfer can Saab actually provide? What is unique about the Gripen that Canadian industry does not already understand? The radar isn't Swedish, the engine isn't Swedish, the IRST isn't Swedish. Only about 30% by content is actually Swedish origin.
You might be under-estimating the appeal of having avionics or systems made by other European countries: Sweden being an EU member who has partnerships with manufacturers in other European countries, it could act as a bridge to further defense cooperation.
You can look up the polling data and you'll find that Canadians currently support a pivot towards integrating with (or even joining) the EU... even more-so than strengthening ties with the Commonwealth. I agree that the Eurofighter or Rafale might have a more compelling case... and that the Gripen might be little more than an advance trainer to keep capacities up while waiting for FCAS though.
I feel I've answered all of your other points in previous points.