Fears of significant external threats, imagined or justified, have long been linked to narcissism swelling in a person or excessive power swelling in a government as either grows progressively madder in what they believe is existential self-defense.
These connections have been made for thousands of years. With apologies for the shotgun approach, here's just a few starting points in various fields:
Philosophy: Some 2400 years ago, Plato in The Republic famously analogized between a person's psyche and the orderly or disorderly functioning of a government (see also). Relevant from the past few centuries: the master-slave dialectic in Hegel's The Phenomenology of Spirit, Nietzsche's On the Genealogy of Morality, Heather Marsh's 2020 book The Creation of Me, Them, and Us, and of course others.
Psychology: Observers, Trump's former advisors, and various mental health professionals indicating Trump suffers from narcissism and dementia. See also Hillary Rettig's writings such as "Perfectionism is Rooted in Grandiosity," relevant for its discussion of grandiosity.
Science: A 2011 study in the peer-reviewed journal Social Cognitive and Affective Neuroscience is discussed by Marsh in her 2024 book Abstracting Divinity: "people displaying characteristics associated with the diagnoses of psychopathic and narcissistic disorders have low empathy (affective-perceptual empathy) but average sympathy (cognitive-evaluative empathy) which, along with other research, supports the idea that their supposed impairment is simply an endosocial barrier." In the context of my article, read the preceding sentence's endosocial barrier as meaning hardening against external threats, rather than friendly softening. This hardening closely pertains to the imbalanced swelling of power for the sake of genuine or perceived self-defense in persons or governments confronting real or imagined significant dangers, and it can progress to the point of being crazymaking. Many other scientific studies are relevant as well.
Fiction: Faulkner's 1929 novel The Sound and the Fury (particularly the third chapter), the Star Trek: Deep Space Nine two-part television episode from 1996 -- "Homefront" and "Paradise Lost" -- and plenty of other examples.
Colloquialisms: One for-instance is the common remark in the United States to the effect that, If everyone you meet is an asshole, maybe you're actually the asshole.
Prepared by Douglas Lucas in September 2024 as a footnote, ultimately unused, for his Sept. 22, 2024 article at the Daily Dot: "Election 2024: The future of TikTok and tech policy under Trump versus Harris."