Being able to run on the JVM is not a differentiating factor among lisps. Kawa Scheme and ABCL give you access to Java Libraries.
If you ask me the strengths of Clojure that it is built upon abstraction/interfaces (ie. conj instead of cons) and how it manages hygiene while retaining quasiquotes templates leveraging clj's namespaces. But then again you should probably ask a clojurian instead.
An advantage of Clojure over ABCL is the syntactically nicer Java interoperation and the mechanism to avoid reflection by using "warn-on-reflection" and introducing type hints.
If you ask me the strengths of Clojure that it is built upon abstraction/interfaces (ie. conj instead of cons) and how it manages hygiene while retaining quasiquotes templates leveraging clj's namespaces. But then again you should probably ask a clojurian instead.