The US is NOT authoritarian. If it was, it would actually function. The US since the founding has been a theocratic oligarchy. The "representive government" only represents the top 1%-2% of the population, and only does so about 30%-40% of the time. The 99% else get close to 0% representation.

The US has so many laws and rights, that what you see on paper means nothing. It's all about practice. On paper you have the right for freedom of religion. Or speech. Or press. In reality you do not. If you aren't the proper religion, things don't work for you and you can easily be arrested just because. Just look at the student protests being beaten and shot at by police now for speech and protest rights that don't exist. Press is governmentally censored in many ways, and certain topics are illegal and others get you and your whole organization raided.

It's a failed state. This stupid expression of the country being an "experiment" of governance is ridiculous. Religious elite ruling classes has been the norm for most of human civilization. Even in the Roman Empire, there was a court. With the English Monarchy pre Magna Carta, there was a court. The monarch with absolute power did not act like an idiot, they had council from representives across their kingdoms, the elites with the power and money and titles to meet with the ruler.