It's not just subsidies and mandates, it's large government contracts on maybe not actually needed systems. See the F-35 as an example of this, which has parts manufactured in a majority of states meaning it's impossible for congress to nix this sort of program because it would cost constituents jobs. Also how it makes it harder for congressmen and women to vote against these sorts of deals because it would cost their constituents future jobs.

I don't know about Airbus in particular but this is how it generally work with companies like Lockheed and Boeing.