If you are applying for a junior role, I don't know much about Europe, but in India the defence and security sector often have internship programmes for university students.

Alternatively, same as all other jobs, keep your eye open and make sure your CV and cover letter is catered towards the job.

You don't need to be a misanthrope to work in defence and security. Despite the bad PR, it's comforting knowing that your work is making the world a safer place.