Allow me to relate a longish story, that, I promise, will eventually tie in. The story is about how we learn through experience to gradually become more sympathetic to our fellow humans, and instead of just standing by, to actively engage in times of need and improve lives.
Couple years ago I was changing flights in ATL, the place was a zoo. I was filing into a restroom. Two guys ahead of me in a jostling line was an old fella, clearly lost and addled and confused. I had the "humanity" not to push past him, to give him space to orient himself and be about his business. I congratulated myself on my patience.
But the guy in front of me said to him, "Hey there, friend, can I help?". He took the guy by the arm, lead him into a stall, and gave him a full service number two rest stop. Bless him for that. I learned something that day, which is, sometimes it is your turn to help a guy. Sometimes it is just your turn. This had never previously even occurred to me.
Back to these football players. This unfortunate girl needed protection from a group for whom the idea of protection from themselves seemed unnecessary. Why, they may have thought, would anybody need protecting from a consensual act. Given a choice between participating, standing by passively, or leaving, none of those young men thought fit to step up and protect a drunk girl from a drunk group. And she badly needed that guy to be there and do the right thing and he wasnt there.