Authoritarianism: Heritable or Inheritable? Does it matter?

Personality traits: Stable over time, maybe due more to 

genes (inheritance) than nurture (non-genetic effects)

Heritability vs. inheritability of traits

Heredity refers to the likelihood or probability of traits running in families or groups. A trait can arise from genetics (nature), environment (nurture), or usually some combination of both. Environmental or nurturing influences include habits, behaviors, and various physical, emotional and psychological experiences. Families often demonstrate similar habits and behavior because they tend to share at least some experiences. Heritable traits are not necessarily genetic.

On the other hand, inherited traits are due only to genes. Eye and hair color and blood type are inherited as a gene(s) from each parent. Body shape is both inherited (genetic) and heritable (nurture influenced), but probably mostly influenced by inheritance (genes). Body shape can be affected to some extent by exercise and eating habits, which can arise from heredity, e.g., family habits. In the case of eye and hair color and blood type, nurture effects do not influence those traits. Being a good cook can run in families and that trait might be significantly or nearly all a heritable (nurture) trait with little or no known inheritance (genes) effects.

In a 2016 research paper, The Heritability Fallacy, two researchers wrote about the confusion that commonly plagues the concept of heritability vs. inheritability:

Contrary to popular belief, the measurable heritability of a trait does not tell us how ‘genetically inheritable’ that trait is. Further, it does not inform us about what causes a trait, the relative influence of genes in the development of a trait, or the relative influence of the environment in the development of a trait. Because we already know that genetic factors have significant influence on the development of all human traits, measures of heritability are of little value, except in very rare cases. (emphasis added)

My read of the data is that most human behavior traits arise from a variable combination of nature and nurture and are thus both inherited and heritable. One expert estimated that in terms of political beliefs and behaviors, the average person's politics is is about 35% nature or genes and about 65% nurture. Another estimated it was about 50:50. Clearly, this is not a precise science.

Authoritarianism 

Authoritarianism: a form of government characterized by the rejection of political plurality, the use of a strong central power to preserve a political or social status quo, and reductions in the rule of law, separation of powers, and democratic voting; authoritarian regimes may be either autocratic or oligarchic in nature and may be based on the rule of a party or the military, limited plurality, political legitimacy based on appeals to emotion and characterization of the regime as necessary to combat threats, which are often ill-defined, suppression of political opposition, etc.  

Declining respect for democracy

Some portion of all populations appear to include people with an authoritarian mindset or susceptible to authoritarian appeals (which seem to be usually heavily grounded in dark free speech). In the 1950s and until recently, authoritarianism was generally considered to be a personality trait. recent research suggested that authoritarianism is not stable enough to be a personality trait and instead is a personal adaptation or a trait that is variable.

A 2013 paper, Authoritarianism as a personality trait: Evidence from a longitudinal behavior genetic study, generated data indicating that the source of authoritarianism is mostly genetic and stable enough to be considered an actual personality trait, i.e., it's a genetic problem.[1] The authors wrote:

Authoritarianism has long been conceived of as a highly stable personality trait (Adorno et al., 1950; Altemeyer, 1981), though recent accounts have argued that authoritarianism is too malleable to justify this conception. We provided a test of the trait conception of authoritarianism by measuring its stability in a community sample of twins over a 15 year period, and by identifying the source of any stability with biometric modeling. Our results showed that authoritarianism exhibited a high degree of rank-order stability (r = .74). Biometric analyses indicated that this stability derived primarily from genetic influences, with changes in authoritarianism due to the unique experiences of the individual. In both of these respects, our results were highly comparable to those reported for other personality traits in previous work, indicating support for the trait conception of authoritarianism. .... Our results were consistent with the conception of authoritarianism as a highly stable personality trait. .... This stability was particularly pronounced among the more educated segment of the sample. Among those with 14 or more years of education (N = 285), the correlation between Time 1 and Time 2 scores was .78, significantly higher than the correlation of .64 among those with 13 or fewer years of education (N = 240; p < .001). (emphasis added)

By now it seems clear that the ex-president, most of the GOP leadership and most rank and file republicans are significantly or dominantly authoritarian and that will probably be very hard to change without significant social violence in America, unless more effective non-violent means to address the problem are applied, e.g., maybe pragmatic rationalism, social trust building efforts, etc. If the 2013 data is fundamentally sound, it is reasonable to believe that the authoritarianism the now fascist  GOP and ex-president have unleashed cannot easily be tamped down. 

Decades of radical right lies and polarizing anti-democratic rhetoric (Rush Limbaugh, Fox News, etc.)  plowed and fertilized the ground for the rise of fascism in modern America. The ex-president was the toxic seed that thrived in that ground and acted as a force for authoritarian minds to coalesce around. It took American involvement in World War II to tamp American fascism down. Unfortunately, the radical right has finally succeeded in resurrecting it and bringing it into mainstream political acceptance by the political right,

The data in the 2013 paper is consistent with data analyzing the 2016 election indicating that the single most important factor in driving support for the ex-president was (probably still is) unease over social and demographic changes. Economic complaints and fears were the other co-mingled primary influencer. In view of all the data, one can begin to clearly see how a demagogic authoritarian could have and did overwhelm the old order in the GOP. That old order was replaced with the anti-democratic fascism that now arguably dominates the GOP. It was a smaller step than I thought from authoritarian GOP radical right authoritarianism to full-blown fascist cult authoritarianism.

Maybe it really does matter if authoritarianism and fascism are inherited.

Footnote: 

1. Although authoritarianism is likely to be a significantly or mostly genetic problem, that does not mean the only solution is ethnic cleansing or violence. IMO, social means and institutions, e.g., building social trust, critical thinking and defenses against propaganda, worked in the past to keep it in check and that is what will probably be needed in the future to restore a stable status quo. My brand of politics always looks for non-violent, minimally oppressive-discriminatory means to achieve good political, economic, social and environmental outcomes. 

To make this completely clear: I am not explicitly or implicitly advocating ethnic, ideological or social cleansing by force, coercion or any other non-democratic mean. That is how authoritarians and fascists operate. Pragmatic rationalists like me advocate non-violent, respectful social means to address social problems, including the rise of GOP authoritarianism and fascism. 

Research is into personality and authoritarianism is ongoing and seems to be in a fairly early state of knowledge. A 2020 paper commented: 

Philosophers have long speculated that authoritarianism and belief in determinism are functionally related. .... Authoritarianism and allied variables manifested moderate to large positive correlations with both fatalistic and genetic determinism beliefs. .... openness was negatively related to fatalistic determinism beliefs and agreeableness was negatively related to genetic determinism beliefs. Taken together, our findings clarify the nature of relations between authoritarianism and general personality, on the one hand, and free will/determinism beliefs, on the other, and suggest intriguing intersections between worldviews and personality traits. .... Scholarly recognition of potential links between deterministic beliefs and authoritarian attitudes can be traced to the origins of modern social science. Fromm (1941), a pioneering scholar of the psychology of totalitarianism, posited that individuals seek to “escape from freedom” via authoritarianism in times of uncertainty and threat. Similarly, Adorno and colleagues’ The Authoritarian Personality (1950) highlighted belief in fate, a variant of determinism, as one of 9 personality facets underlying susceptibility to fascist ideology. .... few authors have examined the more basic hypothesis that authoritarianism is related to belief in determinism writ large, the notion that “all events in this world are fixed, or unalterable, or predetermined.” (emphasis added)

Fromm may have arrived at a critically important insight in 1941, years before the full savagery and misery of German and Russian authoritarianism had been fully unleashed on the world. What Fromm seems to have intuited is that authoritarians can't handle changing reality and in their moral cowardice, they regress into force to protect their weak egos.