Is mixing Clojure with Python a good idea?
If you can build both sides to use Data and Pure(ish) Functions to communicate then this should work very well. wrapping your clojure functions in web services that take and retrun JSON (or more preferably clojure forms) should make them accessible to your Python based front end will no extra fuss. 
Of course it's more fun to write it in Clojure all the way through. ;)
If this is a long term project than building clean Functional (as in takes and returns values) interfaces that exchange Data becomes even more important because it will give you the ability to evolve the components independently.
I am working on a big project that involves a lot of web based and AI work. I am extremely comfortable with Python, though my only concern is with concurrent programming and scaling this project to make it work on clusters. Thus, Clojure for AI and support for Java function calls and bring about concurrent programming. 
Is this a good idea to do all the web-based api work with Python and let Clojure take care of most of the concurrent AI work? 
Edit:
Let me explain the interaction in detail. Python would be doing most of the dirty work (scraping, image processing, improving the database and all that.) Clojure, if possible, would either deal with the data base or get the data from Python. I except something CPython sort of linking with Python and Clojure. 
Edit2: 
Might be a foolish question to ask, but this being a rather long term project which will evolve quite a bit and go under several iterations, is Clojure a language here to stay? Is it portable enough?