Democratic presidential nominee Hillary Clinton reiterated her campaign’s bizarre conspiracy theory Monday that Russia is working with Donald Trump to steal the 2016 election.

“If you find a turtle on a fence post, it didn’t get there by accident,” she told journalists on her new campaign jet. “I think it’s quite intriguing that this activity has happened around the time Trump became the nominee.”

Call it the new McCarthyism: from “Vast Right-Wing Conspiracy” to “Reds Under the Bed.”

No, as Charles Lane of the Washington Post pointed out on Fox News’ Special Report later that day, the Russians are no longer communists.

But the structure of the argument works the same way as it did when leftists were being hauled in front of the House Un-American Activities Committee.

Trump is being asked to prove a negative — i.e. that he is not working with the Russians. It is 2016’s version of Obama’s false 2012 claims that Mitt Romney killed a man’s wife, or didn’t pay his taxes.

The Clinton campaign’s Russia conspiracy theory ought to be rejected outright — and Clinton ought to be shamed for making it, for three basic reasons.

1. There is not one real shred of evidence to substantiate the conspiracy theory. Clinton told reporters that Trump “urged the Russians to hack more.” She is referring to a joke Trump told during a press conference — the kind of freewheeling press conference she still refuses to have — after being hectored about Russians allegedly hacking the Democratic National Committee (DNC). That’s all she has: a joke, which is being spun by the media and the Clinton campaign into a smoking gun.

2. The conspiracy theory overlooks Clinton’s own pro-Russia policy. Part of the conspiracy theory rests on the idea that Trump will pursue a policy of engagement with Vladimir Putin. It is a bad idea — but it is an idea first championed by Hillary Clinton herself, when she led the “reset” with Russia as Secretary of State. The result of that policy was Russian aggression in Europe and the Middle East. Pressed by ABC News’ Martha Raddatz on that point, Clinton’s running mate, Sen. Tim Kaine (D-VA), protested that no one in America was responsible for Russia’s actions — negating his own campaign’s argument.

3. Clinton allowed Russia to control 20% of U.S. uranium, thanks to a Clinton Foundation donation. One of the most damning allegations to emerge from the Clinton Foundation scandal is that the Secretary of State allowed 20% of America’s uranium to be sold to a Russian company controlled by the Russian government after a timely payment to Bill Clinton for a speech and several donations to the family charity from the company’s chair. Given actual evidence of Clinton working with Vladimir Putin to undermine America’s national interest, she ought to be wary of accusing others.

It may be true that Russia hacked the DNC, and it may even be true that Russia wants to interfere in the election on Trump’s behalf (or not).

But presuming Trump to be conspiring with Russia is pure McCarthyism — and deserves to be called that.

Joel B. Pollak is Senior Editor-at-Large at Breitbart News. His new book, See No Evil: 19 Hard Truths the Left Can’t Handle, is available from Regnery through Amazon. Follow him on Twitter at @joelpollak.