Recursion is the fundamental looping facility. Every kind of loop can be translated to recursion. That's why I think all languages that should be compiled to has it.

Translating one looping facility to another is usually very painful. Translating a looping facility to recursion is less painful :)

Edit: as an exanple: try compiling the common lisp loop macro to python for loops. I am not even sure it is possible. Compiling it to recursive functions (of which python lacks the tail recursion optimized kind) is however a pretty straightforward, but still very much nontrivial, problem.