Clojure actually removes a lot of things from lisp. So it might not be a very good analogy to c and c++. For eg clojure doesnt have an object oriented framework like CLOS, does not have reader macros, currently has a much smaller set of inbuilt functions. Not to say it hasnt added new stuff, it has, eg persistent data structures, deep integration with the jvm. Also importantly all valid lisp programs are not valid clojure programs. In short, its a clean break from lisp which carries the useful ideas and the spirit of lisp forward.