It's easy to criticise inaction in the face of these all-too-common events, but hard reality must also be faced. Many well-meaning interventions have resulted in the Good Samaritan becoming the victim.
Intervening against a possibly drunk, large and powerful raging man is plainly foolish. But I'll tell you who can: women.
Some years ago, I was guest speaker at a police passing-out parade. During the cocktail party, I chatted with a graduate barely 5ft (1.5m) tall. When I sat down for dinner, I expressed my surprise to the Police Commissioner at the size of some of the graduates. He exploded. "Bloody human rights nonsense. The days of the minimum height and maximum age are gone."
I mentioned the girl whom I chatted to, adding she would be useless in a melee. The commissioner told me that, to the contrary, women are incredibly effective and never more so than in so-called "domestics".
These are of great concern to the police, understandably given the number who have been murdered by some cowardly oaf whose manhood is apparently threatened when a large policeman turns up while he's thrashing his wife and children. But seemingly they turn to lambs if, instead, a peanut-sized policewoman intervenes.