Very basic clojure Hangman using recursion

Hangman.clj

(ns hangman.core
  (:gen-class)
  (:require [clojure.string :as str]))

(defn is_char_in_words?
    "Is the char in the words?"
    [ch words]
    (if (= ch "")
        false
        (> (.indexOf words ch) -1)
    )
)

(defn char_to_draw
    "Chooses whether to draw a _ or a char"
    [ch guesses]
    (if (is_char_in_words? ch guesses)
        (str ch " ")
        (str "_ ")
    )
)

(defn get_board
    "Gets the current board"
    [words guesses]
    (str/join (map #(char_to_draw (str %) guesses) (seq words)))
)

(defn draw_board
    "Draws the current board"
    [words guesses]
    (println (get_board words guesses))
)

(defn have-a-go
    "Has a go"
    [words guesses chances]
    (draw_board words (str/join guesses))
    (if (is_char_in_words? "_" (get_board words guesses))
        (if (= 0 chances)
            (println "FAIL!!!!")
            (do
                (println (str "Guesses: " guesses))
                (println (str "Chances: " chances))
                (println "Enter your guess:")
                (let [guess (read-line)]

                    (let [new-guesses (conj guesses guess)]
                            (if (is_char_in_words? guess words)
                                (have-a-go words new-guesses chances)
                                (have-a-go words new-guesses (- chances 1))))
                    )
                )
        )
        (println "AWESOME!")
    )
)

(defn game
    "Runs a game of hangman"
    []
    (do
        (print "Enter your words: ")
        (flush)
        (have-a-go (read-line) [] 5))
)

(defn -main
  "I don't do a whole lot ... yet."
  [& args]
  (game))