Ballet Dancers as Enforcers?

On NRO's Corner, Lisa Schiffren writes:

(Rahm Emmanuel trivia watch: FWIW, he will surely be the first White House chief of staff who started life — after Sarah Lawrence, as Cliff May notes — as a ballet dancer. And who thinks of ballerinas as thuggish enforcers?)

That seems less strange after reading “Dark Night of the Soul” by James Blish, in which a revolt in an artist's colony orbiting Jupiter is helped by the intimidating presence of ballet dancers (the strongest people around there) armed with sculptor's knives.