"For conservatives his arguments on human nature that conclude that we are inherently brutish and violent and cannot be allowed to rule ourselves are very attractive."

I really hope you are European. What you said is true of (most) European Conservatives. If you are an American, that is the most incorrect thing I have read all week. American Conservatives are the exact opposite of what you describe.

The core of the American right wing is to reject the idea in your quote in all ways. The individual is the highest ideal in libertarian ideology. This is why the US Republicans never, ever align themselves with political parties in other countries. They have a completely different set of beliefs. And for some weird reason Europeans completely ignore this and will even react violently when it is explained to them. Its just weird...

Conservatives draw towards authoritarian or "strong" leaders reflect this idea, while its at odds with the more individualistic philosophy. There is a cognitive dissonance there.

The American Right of the 80's through 00's maybe. But today's right wing seems more authoritarian than anything post-Trump. There's this weird sort of thirst for a strong-man government on the right that seems to run counter to the individual liberty arguments they tend to make. I don't get it and I wish it made sense.

Sure, the US is weird as it is a one-party state that constitutionally and supposedly is fundamentally liberalist, which has the effect that the only viable collective politics becomes fascist or fascism adjacent. Hence the insistence on historical revisionism, genocidal military campaigns and slavery-like institutions.

To the extent US politics is libertarian it is also very selectively so, it does not extend to all people and discards individualism as a universal ethos, either explicitly or by blaming its victims.