One of the most annoying, horrible, and downright irritating
situations you'll ever run into socially is someone suddenly inveighing
against you with emotionally-charged, finger-pointing, judgmental
arguments.

These attacks are usually unexpected when you run into them, and
they'll frequently catch you off guard. They can be confusing to know
how to respond to if you're more accustomed to calm, cool-headed
debates about the merits and drawbacks of a specific subject - then
suddenly here's someone sandblasting you with hatred and unadulterated
emotion. I'm sure you've experienced it at some point or another:
“People like you are the lowest kinds of people there are! You
think you can just take whatever you want and not have to suffer the
consequences! You think of no one but yourself!”
Suddenly, you're so deeply on the defensive trying to prove these
accusations levied against you are untrue, that you end up effectively
putting your hands up and saying, "Whoa, hey, stop, that's not true at
all!"
Morality attacks also usually have
a powerful communal effect, with any bystanders to the argument
usually feeling either a) swept up in the argument and equally enraged
and emboldened, or b) so afraid of being castigated themselves that
they either just agree out of fear, or they remain quiet and let things
unfold, not wanting to get in the way of an onrushing freight train.
That means that when someone starts hitting you with moral
superiority, you need to be quick on your feet to not get quickly cast
out as whatever you're being labeled as - and the way to do that, of
course, is fighting fire with fire: you
must use moral superiority right back.