President Trump did the right thing by finally rejecting Vladimir Putin’s outrageous proposal to let his intelligence goons question US citizens, including a former ambassador to Moscow. Let’s hope he truly understands how unacceptable the idea is.

White House Press Secretary Sarah Huckabee Sanders Thursday claimed Putin had made the proposal “in all sincerity.”

Nonsense: He made it as payback for special counsel Robert Mueller’s indictment of 12 Russian intel officers for trying to influence the 2016 presidential election.

And because he’s intent on punishing those responsible for the 2012 Magnitsky Act, which can be used to sanction human-rights violators — and which Putin may fear could target his own offshore accounts.

That law has been an unqualified success, squeezing Putin’s regime and shining a spotlight on its brutality. And Putin’s livid.

Which is why he has targeted investor Bill Browder, who was largely responsible for the law’s passage, along with former Ambassador Michael McFaul, who was critical of Putin during his stint in Moscow.

When Trump initially called Putin’s proposal an “incredible offer,” it rightly left nearly everyone dumbfounded. Trump’s own State Department called it “absurd,” with Secretary Mike Pompeo stating flatly: “That’s not going to happen.”

Yet Trump failed to rule out the offer for days (never mind that he’d have no legal right to turn over anyone to Russia, even just for questioning).

It’s a mystery why he didn’t just say from the outset what everyone else in his administration understood: Under no circumstances will America let Putin’s thugs interrogate Americans, especially about politically motivated charges.

Trump should’ve nixed Putin’s proposal without blinking an eye.

Instead, he raised eyebrows — and gave his own enemies more ammuntion to use against him.