Threats at Home and Abroad: Interstate War, Civil War, and Alliance Formation User GnomonConquest, in the International Relations subreddit, 11 Aug 2021
IO study: "An empirical analysis of alliance formation from 1946 to 2009 shows that while external threats motivate the formation of defense pacts, internal threats encourage the formation of consultation pacts." User smurfyjenkins, in the International Relations subreddit, 05 Apr 2021