I'd go with that... it's very much a product of its times.
Agreed. When the movie played in the Boston area in '71-'72, It was rated "X", and for a short time, bore the "Banned in Boston" legend. (Most members here are probably not old enough to remember the "X" rating. It simply meant that no one under eighteen was admitted under any circumstances to a movie that bore this rating. ) The movie was very controversial. "Everyone needs to see this movie!" vs. "This movie is total garbage, and the book should be banned", were heard a lot. You were considered "rebellious" if you had read the book, and really rebellious if you went to see the movie.
I do indeed consider it to be a classic. It helps I think, if one reads the book before viewing the movie. I seem to remember barnes and noble releasing an edition recently, that contains the missing chapter 21. I could be mistaken.
Today, the sex and violence portrayed in the movie really don't shock anyone.
Sort of off-topic: The "Banned in Boston" bit comes from the time when the Boston archdiocese and and old (now long defunct) organization called "The watch and ward society" were actually able to censor books, publications, and movies for material they just didn't like. It turned into a marketing tool. I think the last movie to be "banned in boston" was Caligula, which also starred Malcolm MacDowell, oddly enough.
Oh yeah, how I got to see "Clockwork Orange" at age 15: The old fashioned way. A friend at the theater let me in.
The Theme is in my iTunes library.