The imperativeness of Racket really doesn't come so much from the *! functions, but instead things like `begin` which explicitly sequence program statements in such a way that only allows them to interact via external mutable state.

I have a feeling we are on yet different definitions of imperative and such.

    (define x 3)
    (display x)
    (set! x (add1 x))
    (display x)

is about as imperative as they come, by my definition. And not a begin in site.

Yeah, there's sort of an implicit begin around the whole thing, though.