Former Ku Klux Klan leader David Duke registered as a Senate candidate in Louisiana on March 22, 2016. (Max Becherer/AP)

A far-right group whose anti-Muslim videos were retweeted by President Trump last month has been kicked off Twitter in what the social network describes as a new effort to “reduce hateful and abusive content.”

Twitter suspended Britain First and other accounts on Monday but conspicuously spared former Ku Klux Klan leader David Duke and prominent white nationalist Richard Spencer.

Spencer, seemingly surprised that he was still permitted to tweet, tweeted that he couldn't figure out why some bit players in his “pro-white” posse had been banned while the accounts of better-known figures such as Duke remained active.

Twitter's new standards are indeed hard to figure out, owing in part to the subjectivity inherent to labeling hate speech.

For example: In a blog post on Monday, Twitter said it prohibits “content that glorifies violence or the perpetrators of a violent act” and explained that “this includes celebrating any violent act in a manner that may inspire others to replicate it or any violence where people were targeted because of their membership in a protected group.”

Enforcing such a policy can require multiple judgment calls. The motive behind a violent act is not always clear. What exactly constitutes glorification? And what marks a Twitter user's glorification of violence as likely to spur others toward action?

The hashtag Spencer referenced, #TwitterPurge, quickly filled with charges that Twitter is trampling free speech — conservative speech, in particular.

Yet Twitter also drew criticism from people who contend that the platform's crackdown does not go far enough. During a previously scheduled appearance before British lawmakers on Tuesday, Twitter Vice President Sinead McSweeney was challenged by Home Committee Chairwoman Yvette Cooper, who vented her frustration that certain tweets have not been removed from the platform.

“It's very hard for us to believe that enough is being done,” Cooper said.

Thus, Twitter finds itself taking hits from both sides — simultaneously accused of censoring legitimate discourse and enabling bigotry.

Twitter acknowledged Monday that it “may make some mistakes” while trying to strike the right balance and said it will “evaluate and iterate on these changes.” As the company does so, it is worth remembering something about Duke and Spencer: They are masters of coded messaging — of insinuating themselves and their ideologies into the mainstream through euphemisms and professional appearances.

The Anti-Defamation League described Duke's tactics in a 2000 report:

As grand wizard of the Knights of the Ku Klux Klan in the 1970s, David Duke urged Klan members to “get out of the cow pasture and into hotel meeting rooms.” For the past 25 years, he has increasingly attempted to follow his own advice by using code words and increasingly disguising his ideas behind more mainstream conservative-sounding rhetoric . . .

In an attempt to demystify Klan ritual, he renamed the position of grand wizard “national director” and referred to cross burnings as “illuminations.” In 1980, Duke resigned from the KKK and formed a “political organization” to promote the cause of “white rights.”

When The Washington Post profiled Spencer last year, reporter John Woodrow Cox wrote that “from a distance, almost everything about him appears as innocuous as the term 'alt-right' — and that's by design. Spencer heads a pair of organizations with unremarkable names: the National Policy Institute and Radix Journal. He dresses in three-piece Brooks Brothers suits, gold-coin cuff links and $5,000 Swiss watches, and he sports a swept-over hipster haircut known as a 'fashy' (as in fascist).”

Al Letson, host of the public radio program “Reveal,” remarked while interviewing Spencer last year that the white nationalist has “this great sheen.”

“I've done some reading on you,” Letson told Spencer. “Just a little bit of research and watched a couple of videos. And you're a handsome guy, man, and you're well put together. You're really smart. And I'm actually enjoying having this conversation with you. But what's the difference between you and the racists that, like, you know, hung people up from trees? . . . I'm saying to you that your ideas sound just like them, except you wear a nice suit and you can speak to me directly.”

The point is that Spencer and Duke — who boast 130,000 Twitter followers, combined — can probably polish themselves into compliance with whatever rules Twitter establishes while continuing to spread their messages in subtle ways. People counting on Twitter to shut down Spencer and Duke might focus on exposing them for what they truly are, instead.