Drones have an extensive use in defense industries and just because the west produces less consumer models doesn't mean the tech isn't there. It will take banning DJI for them to quickly see they're not as far ahead as you imagine. It will probably cost more to buy though.
The thing is, consumer drones are widespread and generate a lot of data. Not just about the general performance of the drone or AI (like Tesla does), but also about weather conditions such as wind, or population densities that are classified by the drone's AI. All of this can be fed into massive data warehouses for later analysis - and the more drones one has, the better the quality of the derived data. In turn, that data can be used by the military for all sorts of planning and general intel collection.
Given that DJI has 76% of the market, the largest competitor (shockingly Intel - no idea they made drones?!) has 4% and the rest barely hits ~3%, it's safe to assume that no competitor comes even close to DJI [1].
Looks like Intel sold their Drone business...to Elon Musk's brother. Interesting development although it seems like they were focused on providing light shows. Explains why we are seeing these light shows at Tesla unveiling events ha!