(CNN) As the United States-backed government in Afghanistan fell to the Taliban and US troops raced to leave the country, White supremacist and anti-government extremists have expressed admiration for what the Taliban accomplished, a worrying development for US officials who have been grappling with the threat of domestic violent extremism.
That praise has also been coupled with a wave of anti-refugee sentiment from far-right groups, as the US and others rushed to evacuate tens of thousands of people from Afghanistan by the Biden administration's August 31 deadline.
Several concerning trends have emerged in recent weeks on online platforms commonly used by anti-government, White supremacist and other domestic violent extremist groups, including "framing the activities of the Taliban as a success," and a model for those who believe in the need for a civil war in the US, the head of the Department of Homeland Security's Office of Intelligence and Analysis, John Cohen, said on a call Friday with local and state law enforcement, obtained by CNN.
Cohen said on the call that DHS has also analyzed discussions centering on "the great replacement concept" a conspiracy theory that immigrants, in this case the relocation of Afghans to the US, would lead to a loss of control and authority by White Americans.
"There are concerns that those narratives may incite violent activities directed at immigrant communities, certain faith communities, or even those who are relocated to the United States," he added.
Far-right extremist communities have been invigorated by the events in Afghanistan, "whether by their desire to emulate the Taliban or increasingly violent rhetoric about 'invasions' by displaced Afghans," according to recent analysis from SITE Intelligence Group, an American non-governmental organization that tracks online activity of White supremacist and jihadist organizations.
Some people are commending the Taliban's takeover as "a lesson in love for the homeland, for freedom, and for religion," SITE said in its weekly bulletin on far-right extremists.
Neo-Nazi and violent accelerationists -- who hope to provoke what they see as an inevitable race war, which would lead to a Whites-only state -- in North America and Europe are praising the Taliban for its anti-Semitism, homophobia, and severe restrictions on women's freedom, SITE found.
For example, a quote taken from the Proud Boy to Fascist Pipeline Telegram channel, said: "These farmers and minimally trained men fought to take back their nation back from globohomo. They took back their government, installed their national religion as law, and executed dissenters ... If white men in the west had the same courage as the Taliban, we would not be ruled by Jews currently," SITE found.
"Globohomo" is a derogatory word used to insult "globalists," the term used by conspiracy promoters to describe their enemy (the evil global elite who control the media, finance, political system etc), according to SITE.
For months, US officials have warned that domestic violent extremism is the greatest threat to the homeland, pointing to the January 6 attack at the US Capitol as a stark illustration of the potential for violence that can occur when conspiracy theories and false narratives flourish.
A significant part of the current threat environment comes from individuals who are influenced by what they see online, Cohen told CNN in an interview last month.
At this time, Anti-Defamation League's Center on Extremism, is not seeing any observed credible threats, or mobilization of online extremist activity, but is concerned that the current online rhetoric highlights ideological concerns and possible threats to public safety, said Joanna Mendelson, associate director of the center.
Extremists often take current events and weave them into their own narrative and worldview, said Mendelson, which is what is taking place in the aftermath of the withdrawal from Afghanistan and amid the humanitarian and military crisis.
"They're taking the same kind of core tropes and themes, and kind of bigoted views of the world, and injecting them into this current event," Mendelson told CNN.
There has been a lot of Islamophobia and xenophobia echoed by White supremacists and anti-Muslim activists, claiming that public safety and national security is threatened because they see refugees through a stereotypical lens as being dangerous criminals or terrorists, according to Mendelson.
A core conspiracy guiding White supremacist ideology is the "the great replacement," the belief that ultimately, the White race is facing its ultimate extinction, she said.
There is also "almost this infatuation and admiration" of the Taliban, Mendelson said, pointing to the notion that an under-equipped insurgent group could successfully defeat a global power.
"The fact that the Taliban at the end of the day could claim victory over such a world power is something that White supremacists are taking note of," she said.
Megan Squire, a professor of Computer Science at Elon University, who researches US-based domestic extremist groups, has seen three main Afghanistan-related trends emerge in platforms used by a range of far-right groups, such as White supremacists, neo-Nazis and Proud Boys-style forums.
The first narrative to emerge among the extreme far-right groups was "reveling in the humiliation" of the US withdrawal from Afghanistan as images emerged of Taliban fighters taking over city after city, along with US equipment left behind, Squire said, both celebrations of defeat and feelings humiliation as Americans.
When one goes deeper into the neo-Nazi groups, you see some celebration of the Taliban, usually related to extremely misogynistic or extremely anti-Semitic discussion, she added.
This type of cross-ideological praise has historical precedent, according to Squire, citing as an example, a meme that circulated in neo-Nazi communities during a particularly misogynist period about "white Sharia," the concept that women should be treated the way the Taliban treats women.
There have been recent examples of right-leaning groups supporting movement overseas that appear ideologically distant. For instance, earlier this summer, QAnon and Donald Trump-supporting online forums celebrated the deadly military coup in Myanmar and suggested the same should happen in the United States so Trump could be reinstated as President. CNN also spoke to followers of the former President in Ventura, California, in February who said they wanted to see a Myanmar-style coup happen here.
However, the most common narrative is around the idea that the US is "importing the Taliban" through the relocation of Afghans and that Afghan refugees are too different to become real citizens, according to Squire.
"It's really an anti-Muslim idea, anti-immigration idea," she said.
The Pentagon announced Monday that the last US military planes left Afghanistan, departing after weeks of chaotic and deadly evacuation efforts that were punctuated by the devastating suicide attack last Thursday that killed more than 170 people, in addition to the 13 US service members who were also killed.
Some of the Afghanistan narratives are focused on "the Taliban did it right" and that it should be a "lesson learned" for how we should operate in the US, a US law enforcement official told CNN about the rapid rise of the Taliban as the US withdrew troops.
"That's got us a little concerned," because it suggests an escalation in violence, the official added. For example, there were references to the fact that only 80,000 Taliban were able to defeat an Afghan army of several hundred thousand supported by the US, the official said.
As of February, the Afghan forces numbered 308,000 personnel, according to a United Nations Security Council report released in June -- well above the estimated number of armed Taliban fighters, which ranged from 58,000 to 100,000, CNN previously reported. Though number of Afghan forces has been considered by many to be inflated.
"There are some significant discussions," in which people are expressing support of what the Taliban has done and are looking at it as an example of what anti-government extremists should be doing in the US, the official said, adding that the reaction has been a "little bit surprising."
In Europe and the US, there has also been an "outpouring" of anti-refugee commentary from White nationalists and Neo-Nazis responding to the Taliban's takeover, SITE found.
Commentary on anonymous forums has been particularly violent, according to SITE, which found users discussing taking up arms, and in one case, threatening attacks on refugee assistance organizations in Florida.
The hateful rhetoric is similar to that seen amid Libyan and Syrian refugee waves in the 2010s, which paved the way for violent terrorist attacks in Christchurch and Pittsburgh, according to SITE.
Amid anti-immigrant sentiment, DHS officials have been bracing for whether Afghans themselves will be targeted once they land in the US and are resettled here, a DHS official previously told CNN.
"Will they be the potential target? Will Afghans themselves become targets?" the official said, noting the concern.