I've wondered about just SAMs and MANPADs as an alternative to any new fighter jet. We can't really trust the F-35 and the alternatives (the Gripen E) might not be survivable, depending on a bunch of data I don't have.
Sure, they can't be used offensively, but that's not the main thing I worry about in the near future.
Until someone comes up with a very compelling anti-drone countermeasure, drones are basically the ideal weapon for a battlefield. Cheap, mobile, can loiter, good recon, etc.
Sort of? Existing software isn't smart enough to fight a battle on it's own, and electronic warfare is a real thing that makes communications hard. In a full-blown war situation there's appeal in having a human being in a cockpit close to possible targets.
The things we worry about in Canada are more specific, though. For example, we probably don't need long-range bombers of our own.