"The future of Lisp, if it has one, is Clojure."
It's not the Clojure part that got you downvoted, as that would have been a valid argument, seeing how sweet clojure is. I think it's the "if it has a future" part. Anyone even remotely aware of programming languages will tell you Lisp has a future, in the same way Algebra does. It's the simplest representation of computable functions, and it has existed, on paper, at least since 1930, and as an implementation since 1958. It's a gateway drug to lambda calculus ,combinatory logic, complexity theory, computable functions and CT, the entire FP field, symbolic logic, formal semantics, compiler construction, and a host of other non-sexy, but essential fields of study.
LISP: This is the apex of untyped programming with nested scoping and metadata manipulation. It's at the end of the line, not because of lack of potential, but it's so simple and powerful than any improvements to it can be implemented in LISP itself without affecting the core language. In 100 years, after the last C and C++ programmers are long gone, there will still be LISP enthusiasts. But don't expect large-scale software development to happen this way.
So yes, Lisp has a future in that it epitomizes a certain programming paradigm, but as a language with real production significance it has a very hard road ahead, and will need all the advantages that a single-implementation JVM/CLR dialect like Clojure can provide.
You'll notice that hardly any of the companies spawned by Y-Combinator, the ultimate Lisp cult, actually built their systems in Lisp.
You would be stupid to think YC companies amount to anything in the global economic radar. One DoD contract is more profitable than all their revenues combined.
Take a step back, get yourself a phone book and scan it, read international economic reports; none of what we're doing is the apex of human innovation. The AK47-wielding fucktards in the Congo have more global influence than all the startup founders combined. In the grand scheme of things, computer programmers, their bosses, project managers, and employers are the janitors of the world economy. We're call-center operators, glorified with a smidgen of science. And YC "com'nies" have less than $50k standing between them and obscurity; that's less than what the typical restaurant owner spends on kitchen renovations.
Wake up and small the coffee; it's a 99-cent 7/11 re-fill, and I hope you like it.
The really smart Lispers like Peter Norvig recognized Lisp for the lost cause it is and moved on to build companies like Google. Maybe you've heard of it? People have been solving hard problems for decades without the "magic" of the Lisp primadonnas.
I am currently testing it with ABCL. Common Lisp on the JVM. I would say about 80% of Common Lisp libraries work on the JVM unchanged, and the rest (CFFI/UFFI stuff) we're patching them manually.
It's pretty sick stuff. It's Lisp, but it can call 100% of Java libraries. I made a quick "breadth-first" conquest of Java libraries and I seem to be able to use everything; J2SE, J2EE, Android and JavaFX. I am still learning Java, but I can safely say that Java apps and libraries are almost 100% usable via Lisp.