They are one of the only bands where you can play a song from their early albums and later albums side-by-side, and not notice any real difference in sound. they haven't evolved. Which is a good thing! No 180 degree turns into disasterous experimentaion, no "finding Bhuddism", "the maharishi", or any other excursion into "spirituality" that ultimately screws up the music...
They are like a big-assed, beat up, smoke belching muscle car that just keeps running and running. Shooting flames out of the exhaust, waking neighbors, scaring old people and small children, AC/DC keeps on rocking down the Highway to Hell!!!
AC/DC also only wrote one political song that I know of.
"Burnin' Alive" which was a shot at Klinton.