
https://www.bruegel.org/analysis/defending-europe-without-us-first-estimates-what-needed

https://www.project-syndicate.org/commentary/germany-european-defense-free-riding-by-adam-tooze-and-shahin-vallee-1-2018-05?utm_source=Project+Syndicate+Newsletter&utm_campaign=beb150cda9-sunday_newsletter_20_5_2018&utm_medium=email&utm_term=0_73bad5b7d8-beb150cda9-105765449

https://www.project-syndicate.org/commentary/european-defense-after-nato-by-joschka-fischer-2019-11?utm_source=Project+Syndicate+Newsletter&utm_campaign=97304e2f9b-sunday_newsletter_8_12_2019&utm_medium=email&utm_term=0_73bad5b7d8-97304e2f9b-105765449&mc_cid=97304e2f9b&mc_eid=0c8d9ddf15