People who are exposed to Mark Twain only through Tom Sawyer/Huck Finn/A Connecticut Yankee/etc. works usually think of him as a "fun" author.
But he had one of the most incisive and intellectual minds of his times, which was biting in its criticisms/satire of American and the larger Human civilization. Everybody (but Americans especially) should read his set of essays titled; On The Damned Human Race for edification.
I often wonder what he would think of current-day American society and so-called democracy. He actually coined the term "Gilded Age" to highlight the covering of everything rotten/corrupt with a superficial sheen so as to sell it to the masses. If that doesn't describe today's society i don't know what does.
Read, The Lowest Animal (aka The Damned Human Race) by Mark Twain - https://www.thoughtco.com/the-lowest-animal-by-mark-twain-16...
And so I find that we have descended and degenerated, from some far ancestor (some microscopic atom wandering at its pleasure between the mighty horizons of a drop of water perchance) insect by insect, animal by animal, reptile by reptile, down the long highway of smirchless innocence, till we have reached the bottom stage of development – nameable as the Human Being. Below us – nothing.