The word on Cooper is that he’s feisty and mean and willing to fight (as his drunken . . . supposedly . . . comments at a Kenny Chesney concert would indicate). Per a league source, Cooper has been involved in situations like that in the past, and he has responded a lot more forcefully than he did on Thursday.
Per the source, multiple players and executives have acknowledged that Williams was lucky Cooper had no choice but to stand down.
In this specific case, Cooper didn’t retaliate forcefully, presumably because of his involvement in the ugliest controversy of the preseason. But for that entanglement, Cooper would have tangled with Williams in a far more aggressive way.