There are many encouraging published studies. Europe: https://www.imperial.ac.uk/news/180592/european-cooperation-could-provide-more-stable/ https://www.imperi

There are many encouraging published studies. Europe: https://www.imperial.ac.uk/news/180592/european-cooperation-could-provide-more-stable/ https://www.imperial.ac.uk/news/180592/european-cooperation-... US: https://www.cmu.edu/ceic/assets/docs/publications/published-papers/2017-and-2018/handschy-et-al-2017.pdf https://www.cmu.edu/ceic/assets/docs/publications/published-...