Hubris syndrome: An acquired personality disorder? A study of US Presidents and UK Prime Ministers over the last 100 years. https://academic.oup.com/brain/article/132/5/1396/354862.
This also gave rise to a book Hubris Syndrome, David Owen, Methuen 2012 (paperback ISBN: 9780413777270).
Part 3 Consider - On Power - The difficulties of ends and means - Dangers and Difficulties