there are so many great lines in that film, and in fact it is probably the film i've seen more often than any other. i love it, even the crap bits*. But actually i seem to be the only one who doesn't much love the 'crush your enemies' line.
It's just a paraphrase of a famous quotation of Ghengis Khan's, and is used to illustrate Conan's central asian martial arts training. It doesn't really reflect Conan's character.
Far inferior to "Heeee didn't caaare anymoooore"
*crap bits delightfully include Conan and Subotai prancing across the desert, and the meaningful moment in the sex scene
edit: it is my suspicion that a real new Conan cannot be really made until we have mastered human cloning and can create a new young Schwarzenegger for the role