Have you ever personally tried to optimize a Lisp program? It isn't terribly difficult, as optimizing goes. You have full access to control flow as far down as

Have you ever personally tried to optimize a Lisp program? It isn't terribly difficult, as optimizing goes. You have full access to control flow as far down as goto, and you can use machine integers and arrays. Depending on the implementation, you may even be able to use explicit pointers. Obviously it isn't any closer to modern hardware than C, but as far from the hardware as the high-level parts are, the low-level parts are pretty reasonably close.