Twice in just a few hours Saturday, President Trump and his representatives offered textbook examples of the fog-making rhetorical response known as the non-denial denial.

Asked during a Fox News interview whether he was a Russian agent (as the FBI suspected, according to a blockbuster New York Times story), Trump harrumphed, “I think it’s the most insulting thing I’ve ever been asked. I think it’s the most insulting article I’ve ever had written, and if you read the article you’ll see that they found absolutely nothing.” (Trump gave a more direct denial on Monday.)

A few hours earlier, White House press secretary Sarah Sanders had this reply to a Washington Post article that found that Trump had concealed notes of his meetings with Russian president Vladi­mir Putin from even his closest advisers: “The Washington Post story is so outrageously inaccurate it doesn’t even warrant a response. The liberal media has wasted two years trying to manufacture a fake collusion scandal instead of reporting the fact that unlike President Obama, who let Russia and other foreign adversaries push America around, President Trump has actually been tough on Russia.”

Like all non-denial denials, both responses were forceful, even emotional in tone. But neither really answered the question.

That’s exactly how a non-denial denial (or NDD, if you will) is supposed to work. It suggests the speaker is responding forthrightly, without really confirming or rejecting the claim.

NDDs aren’t technically lies, but they are evasive and obfuscating. By seeming to dispute a statement without actually doing so, an NDD can raise doubts about the veracity of a damning statement. They have the added benefit of letting the non-denial denier off the hook if and when more facts emerge that confirm the original report. The denier, after all, never actually said the initial report was wrong, so he or she can’t be called on a blatant lie later.

●When The Post reported that Trump had told lawmakers in a private meeting last January that he opposed admitting more immigrants from “shithole countries,” White House spokesman Raj Shah issued a statement that neither denied nor confirmed the comment. “Like other nations that have merit-based immigration, President Trump is fighting for permanent solutions that make our country stronger by welcoming those who can contribute to our society, grow our economy and assimilate into our great nation,” Shah said.

●Following news reports that Trump intended to replace national security adviser H.R. McMaster with John Bolton in March, Sanders tweeted, “Just spoke to Potus and Gen. H.R. McMaster. Contrary to reports, they have a good working relationship. There are no changes at the NSC.” There weren’t then; Bolton replaced McMaster four days later.

●McMaster himself provided non-denial cover for the White House after The Post reported last year that Trump had leaked details of a classified operation against the Islamic State during an Oval Office meeting with Russian ambassador Sergey Kislyak and foreign minister Sergei Lavrov. “The story that came out tonight, as reported, is false,” he said, adding, “At no time were intelligence sources or methods discussed. And the president did not disclose any military operations that were not already publicly known.” But the story never said Trump disclosed nonpublic military operations or discussed “intelligence sources or methods.” McMaster’s statement never cited anything specific in the story that was false.

The “non-denial denial” phrase itself appears to have entered the lexicon during the Watergate era of the mid-1970s.

Several sources credit the late Washington Post editor Ben Bradlee with coining it in reaction to statements made by President Nixon and his spokesman about The Post’s reporting.

“As best as I can recall, Bradlee was the first to use the ‘non-denial denial’ language,” said Bob Woodward, who along with Carl Bernstein reported those stories.

At one point, Woodward said, the White House said The Post’s sources were a “fountain of misinformation,” but did not specifically challenge the reported facts. “I recall when I first heard [the phrase], I thought, ‘Ah, Bradlee was giving language to precisely what was happening.’ ”

Woodward said the most artful NDDs are issued with “such force, language and outrage that it sounds like a real denial.” What’s more, as with Trump, the Nixon White House mixed non-denials with outright denials, creating the impression that his administration was actually denying everything.

The Trump White House pushed back on Woodward’s most recent book, “Fear,” with its own nonspecific NDD regarding the book’s many anecdotes about infighting and chaos among Trump’s top officials. In a statement upon the book’s release in September, Sanders said, “This book is nothing more than fabricated stories, many by former disgruntled employees, told to make the President look bad.” (Trump and former White House chief of staff John F. Kelly did, however, issue more specific denials).

As a rhetorical device, NDDs are an updated version of the “red herring” fallacy, the notion that an irrelevant topic is introduced in an argument to divert attention from the original issue, said Edward Schiappa, a professor of comparative media studies at Massachusetts Institute of Technology. In other words, he said, “it’s just another in a long line of strategies of evasion.”

Trump isn’t unique in this, said Dana L. Cloud, a communication and rhetorical studies professor at Syracuse University. “One need only think of Bill Clinton’s reductionist use of a definitional argument when claiming that he did not have sex with Monica Lewinsky,” she said. “It is not a set of tactics unique to Trump or any particular political party.”

But Trump’s NDD’s tend to fit a pattern, said Jennifer Mercieca, a professor at Texas A&M who specializes in American political discourse. His strategy typically involves a combination of denying knowledge of an accusation; denying associating with the people allegedly involved; asking what the victim did to deserve his or her fate; and accusing his accusers, “which is an appeal to hypocrisy.”

As such, Trump’s non-denial denials are different in kind and manner than earlier presidents, according to Rosa A. Eberly, a rhetoric professor at Penn State, because they assert “de facto negative evaluations” of most democratic institutions. “I don’t see [rhetoric of this kind] as an effective strategy for the long game of democracy,” she said.

Trump, Woodward said, “has taken the old Nixon strategy of making the issue the conduct of the press, not the conduct of the president, to new strategic heights. And some of it is working.”