Donald Trump and his campaign aides continue to struggle to distinguish between the Star of David and what the presumptive Republican nominee refers to as “a plain star.”

While it is surely troublesome when a candidate for president has trouble distinguishing between the six-pointed Magen David that serves as a symbol for modern Jewish identity and the five-pointed shapes that represent the states on the US flag, perhaps we should not be surprised. There is a lot that Trump—who has been stung by charges of anti-Semitism since his Twitter account featured a crude graphic of what sure looked like a Star of David with a pile of money and references to Hillary Clinton as “corrupt”—refuses to recognize about the crude language of hatemongers past and present.

Instead of simply apologizing for sending messages that end up being celebrated by white supremacists, Trump invariably doubles down in defense of terrible tweets. On Wednesday, for instance, the Republican candidate made things worse when he announced that his critics were “sick” and suggested they had “bad tendencies.”

Trump gets caught out on the fascist fringe too frequently for comfort. Carl Bernstein, the Pulitzer Prize–winning journalist who exposed the excesses of Richard Nixon, refers to Trump as “a neo-fascist in the sense of his appeal and methodology that has to do with authoritarianism nativism and [the] incitement which we’re seeing now.” Trump’s campaign, argues Bernstein, has invited “a debate, a historical debate about what fascism was and is and how Donald Trump fits into that picture”—a debate that the author suggests could include a discussion of “authoritarianism,” “despotism,” and “the desire for a strong man who doesn’t trust the institutions of democracy and government.”

The July 4 weekend discussion of Trump’s tweeting, and the concerns expressed by Democrats and Republicans about how, as the New York Daily News notes, the image of the Star of David mingled with piles of cash “made its way from a neo-Nazi message board to his 9.4 million Twitter followers,” has embarrassed some Trump backers. House Speaker Paul Ryan, the candidate’s most prominent supporter, says the Trump campaign needs to “clean up” its social-media messaging. “Look, anti-Semitic images, they’ve got no place in presidential campaigns. Candidates should know that,” says Ryan.

That’s certainly true. But Ryan continues to support Trump, providing cover for a candidate who has shown no inclination to stop walking the authoritarian shadow line.

This is not the first time that Trump has been called out for promulgating neo-Nazi and fascist themes.

Have people forgotten that just a few short months ago Trump retweeted a quote associated with Benito Mussolini?

On the Sunday before Super Tuesday, a Twitter parody account that was named for the fascist dictator who aligned Italy with Nazi Germany—@ilduce2016—tweeted the line to Trump: “It is better to live one day as a lion than 100 years as a sheep.” (Researchers suggest that variations on the line originated with others but that Mussolini adopted it as his own and popularized it during his years in power,)

The billionaire’s Twitter account—@realDonaldJTrump—seized on the @ilduce2016 message and forwarded it to the candidate’s millions of followers.

The realization that he was retweeting what was once understood as a fascist call to arms should have embarrassed, or at least unsettled, the front-runner for the Republican presidential nomination. Indeed, the Gawker staffers who created “the Mussolini bot” say they developed it “under the assumption that Trump would retweet just about anything, no matter how dubious or vile the source, as long as it sounded like praise for himself.”

But Trump did not appear to be embarrassed or particularly unsettled.

When Chuck Todd of NBC’s Meet the Press asked the billionaire about retweeting Mussolini—just two days before a round of primaries and caucuses that would solidify Trump’s claim on the Republican nomination—here’s how the discussion went:

CHUCK TODD: And as you know, right now on Twitter, there is a trending retweet of yours, you retweeted somebody from @ilduce2016, it was a Mussolini quote, but you didn’t know it was Mussolini when you retweeted it, it said, “It is better to live one day as a lion than 100 years as a sheep.” That’s a famous Mussolini quote, you retweeted it. Do you like the quote? Did you know it was Mussolini?

DONALD TRUMP: Sure, it’s okay to know it’s Mussolini. Look, Mussolini was Mussolini. It’s okay to—it’s a very good quote, it’s a very interesting quote, and I know it. I saw it. I saw what—and I know who said it. But what difference does it make whether it’s Mussolini or somebody else? It’s certainly a very interesting quote…

CHUCK TODD: Well, Mussolini is a known fascist… Do you want to be associated

DONALD TRUMP: It’s a very interesting quote, and people can talk about it.

CHUCK TODD: Do you want to be associated with a fascist?

DONALD TRUMP: No, I want to be associated with interesting quotes. And people, you know, I have almost 14 million people between Instagram and Facebook and Twitter and all of that. And we do interesting things. And I sent it out. And certainly, hey, it got your attention, didn’t it?

That it did.

Some of us were struck by the fact that Trump defended his distribution of the inflammatory language that Time magazine in 1943 described as one of the “gaudy phrases” that “studded [the] gaudy years” of the man who imposed a fascist dictatorship on Italy, who historians say “took part voluntarily and knowingly” in the arrest of Jews who were then deported to Nazi death camps, who allied with Hitler and the Axis against the United States and its allies during World War II, and whose forces fought and killed American troops who bravely battled fascism in what Franklin Delano Roosevelt declared to be the great “resistance to world conquest.”

Americans are supposed to have a problem with Mussolini and his associates. A big problem.

There was a reason why historian Stephen Ambrose hailed the struggle against the Axis powers as “The Good Fight.”

Roosevelt referred to that struggle as the “supreme test.”

“It is a test of our courage—of our resolve—of our wisdom—our essential democracy,” said the 32nd president in his final inaugural address on January 20, 1945. “If we meet that test—successfully and honorably—we shall perform a service of historic importance which men and women and children will honor throughout all time.”

The test was met. But the historic significance of the struggle appears to have been lost on Mr. Trump.

When a candidate to fill the Oval Office that FDR once occupied casually describes an expression that’s been linked with a fascist as “a very good quote… a very interesting quote”—and when his campaign casually spreads around what even his supporters describe as anti-Semitic imagery—that’s a measure of the extent to which Trump and his allies have lost touch with this country’s history and with this country’s better angels. The response of an American presidential candidate to questions about whether he worried in any way about people associating him with “a known fascist” isn’t supposed to be “Look, Mussolini was Mussolini” or “What difference does it make whether it’s Mussolini or somebody else?” The response is supposed to be: “Look, I don’t want anything to do with Benito Mussolini or the gaudy phrases that were associated with him.”

Paul Ryan should recognize that it will take more than some editing of Twitter messages to clean up Donald Trump’s act. This is a candidate who seems to think that trafficking in crude stereotypes, making incendiary comparisons and comments, and retweeting lines from dark chapters in history will somehow “make America great again.” Trump is wrong, and those who provide cover for him are equally wrong.