As to where Haskell fits: you're correct, there are many other great languages out there. But I think Haskell is really unique in offering what it does. Clojure, Go, and Erlang are all great in their own regard, but none of them provides the degree of safety that Haskell does. For example, none of them enforce purity, and all three of them freely allow the use of `null` values (which is really quite surprising considering how many problems nulls cause). Clojure and Erlang avoid mutable state like Haskell does (though not to the same degree of rigor) but don't provide the elegant solutions for simulating mutable state that Haskell does with its monads, which almost allow you to "have your cake and eat it too" with state. None of them encourage the degree of abstraction that you'll find in Haskell. Also, at least according to the Computer Benchmark game, Haskell beats all three of them in terms of speed, as well. Haskell's "place" is in generating highly robust code with good performance, and also works as a beautiful language for expressing certain mathematical concepts.
This doesn't make Haskell a perfect language, but it absolutely has a lot to offer that other languages don't. And it's so much different than other languages, that at the very least it can change your perspective on a lot of things.