I always thought critical applications like banking needed compile time type checking. Clojure is neat and all, but it's dynamic.

Clojure supports strong typing if you want it:

https://github.com/Prismatic/schema

https://github.com/clojure/core.typed

These are both libraries that you can choose to use. Both Typed Clojure and Schema are more powerful than Java's type system. By powerful I mean you can declare types and constraints that aren't expressible in most type systems (eg: an object can not be NULL, or a Map or Array must have specific keys or type'd values). Schema is run-time (we only leverage it in development and testing), while Typed Clojure is more akin to compile time.