A Trumpist says: "Something vaguely similar has happened before, so your argument is invalid."
Folks, we already know this is a bullshit argument, but let's take a minute and unpack it.
I mean, murder has happened before. But when someone is charged with murder, the principled legal response isn't "Well, murders have happened before, so this one's no big deal."
When the trumpist says "Obama did it," you're supposed to get defensive.
So instead, respond: "Obama did what, exactly?" Make THEM do the work.
Remember, you're not convincing the trumpist. You're playing to the lurker.
"But what about overzealous social workers?"
"Typical libt*rd. Your [sic] so stupid."
"This is why I don't talk to libt*rds! Stop attacking me, you bully!"
There was never an intent on their part to have a good faith discussion.
Because the trumpist derailer knows the thing you took issue with actually IS bad, indefensible, etc.
So that's the chink in their armor. They KNOW.
(it doesn't matter if it's false and you did care)
Push back on your derailer with questions. Like:
"So, let's clarify: are you in support of this bad thing, right now?"
That's the real question. Not if it happened before or if you cared then.