http://HTTPS://WWW.WHITEHOUSE.GOV/WP-CONTENT/UPLOADS/2017/12/NSS-FINAL-12-18-2017-0905-2.PDF
http://www.rand.org/content/dam/rand/pubs/research_reports/RR1700/RR1786z1/RAND_RR1786z1.pdf
https://blogs.lse.ac.uk/brexit/2021/02/26/future-british-european-security-relations-are-a-matter-of-trust/
https://apps.dtic.mil/sti/pdfs/AD1151522.pdf