Now that the head of Breitbart news, Stephen Bannon, is at the helm of Donald Trump’s campaign, the ideas once housed on the fringe, popular conservative news site are at the center of a presidential campaign.

And no place is this more relevant than on Trump’s signature issue: immigration.

Trump has made immigration the centerpiece of his campaign. To date he has focused his campaign on keeping immigrants out — whether through a physical wall, banning Muslims from entering American borders, or sending undocumented immigrants back to their native countries. But last week he hinted that he might be more like Jeb Bush than anyone thought on immigration. He’s denied such any change — but if he did embrace it, it would amount to a monumental reversal for Trump.

Regardless of this possible policy flip-flop, Trump’s fundamental tone on immigration has not changed, because ultimately his argument — that immigrants disrupt the American identity — is not based in policy, it’s based in sentiment.

This view is key to the marriage between Trumpism and Breitbartism. Breitbartism is an ultra-conservative home of the alt-right, a faction of the Republican Party that is known to hold strong white nationalist leanings. The natural outgrowth is a fearful, immigration-skeptic, and white man’s world view: Trumpbartism.

To truly understand Breitbartism on immigration, I read the last three weeks of immigration articles and reviewed coverage dating back to the start of Trump’s presidential bid, assessing the themes, topics, language and framing.

Here’s what I found: Though Breitbart weaves in some traditional economic anxieties over immigrants stealing Americans’ jobs, the core of its coverage of immigration paints a picture of fear. Immigration is a threat to the literal safety of Americans, and, more importantly, the national and religious identity of white, Christian Americans. This worldview has distinguished Trump from opposing GOP candidates. Even as policies have shifted, he remains true to his messaging that white America’s national identity is at stake.

On Breitbart, immigrants are criminals

For Breitbart, immigration is told through a lens of crime. It’s a brand of coverage more reminiscent of a police blotter: Cases of vandalism, rape, theft, and terrorism involving an immigrant from [insert Hispanic, Middle Eastern, or African nation here].

In other words, immigrants impose an imminent threat to the safety of American society. This is regardless of the fact that immigrants are statistically less likely to commit crimes than native-born Americans. That, however, isn’t on the site.

Consider this slice of Breitbart immigration coverage over the last two weeks:

It’s a simple and direct narrative: Immigrants disrupt the natural order of a safe and quiet American lifestyle. Breitbart stories are loud, anxiety-inducing and consistently focused on making Americans afraid of the dangers immigrants bring to American shores.

Immigration as a war on religious values

Trump opened his campaign calling Mexican immigrants rapists. But since terrorist-related attacks in San Bernardino, Orlando, Paris, and Brussels, just like Trump, Breitbart’s staff has expanded their focus to a different scary set of immigrants: Muslim refugees.

The frame for these stories goes beyond the law-and-order themes of the crime stories. This is a holy war, with a clear message that Islam, "creeping Sharia," and "radical Islamic terrorism" are coming to American shores. Here are some of the headlines:

Breitbart has perfected stories of Muslim refugees joining ISIS. You don’t have to go very far in Breitbart’s coverage to see how this plays out.

Articles highlight the potential weaknesses of the United States’ Southern border not only in terms of undocumented Hispanic immigrants but also "radical jihadists." They highlight reports showing some actual immigrants supporting Trump’s vetting proposals for Muslims and cite a Moroccan Islam expert who "warned that Muslims in Europe view migration as the start of the Islamisation of the continent."

Then there are even immigration articles that argue Islam, as a religion, is just dangerous:

Islamic scriptures say that Islam’s reputed founder, Muhammad, personally ordered or supported the death of many enemies, including at 10 critics and poets, who were the pre-modern equivalent of modern journalist and writers — such as the machine-gunned cartoonists at the Paris-based Charlie Hebdo magazine. Traditionalist or orthodox Muslims says Muhammad is a perfect model of behavior and should be emulated by Muslims today.

Trump’s readiness to paint Islam as an un-American religion has not gone unnoticed this election: He has called for a temporary ban on Muslims entering the country, insisted that Muslim Americans "cheer" terrorist attacks (there is no evidence to this), asserted that Muslim communities harbor terrorists (Muslim communities do alert law enforcement to criminal activity), and that Muslim assimilation in the United States is "close" to "nonexistent" (this isn’t true).

Breitbart’s coverage has aimed to back these claims, propping up a worldview that has not only painted immigrants as terrorists in hiding, but fed into growing fears that the Islam religion as whole is fundamentally un-American.

Conventional economic anxieties over immigration have become an afterthought

The anti-immigration wing of the Republican Party’s message was once primarily economic. They argued that immigrants, willing to work for lesser wages and dependent on welfare programs, are taking American jobs and disrupting the fabric of United States’ work force.

Fundamentally this sentiment still exists — and Breitbart has a fair number of articles articulating the economic costs. But it’s clear that Breitbart doesn’t see the fight over immigration just in terms of economics. Rather, the economic impact has almost become an afterthought, used to strengthen the main argument that immigrants threaten the safety and identity of Americans.

Take for example this recent article on the number of Muslim immigrants entering the United States. The article’s frame incites a religious-based "the Muslims are coming" fear. "Nearly half of the more than 63,000 refugees admitted to the U.S. this fiscal year are Muslim," Breitbart’s Caroline May writes, going on to say that this immigration continued under the Obama administration "despite concerns that terrorist might infiltrate the refugee flow from Syria."

Secondary to that angle, May adds some context alluding to the economic toll of Muslim refugees:

Unlike other types of immigrants, refugees are granted special privileges and protections upon admission to the U.S., including immediate access to welfare benefits, like food stamps, Temporary Assistance for Needy Families (TANF), Supplemental Security Income (SSI), and public housing. Middle Eastern refugees, according to the Office of Refugee Resettlement (ORR), are particularly heavy users of public assistance with 90 percent receiving food stamps and about 70 percent on cash and government healthcare in FY 2013.

This is not to say that Breitbart doesn’t cover the conventional argument against immigration anymore. This month, Neil Munro wrote about the Minnesota state legislature primaries, presumably meant to highlight the irony of two sitting Democrats losing their seats to immigrant political newcomers:

Political jobs held by two veteran Democratic politicians have been outsourced to two young immigrants, underscoring the growing impact of mass immigration on white-collar Americans.

But it’s important to note that Trump — while also running on promises of new and better jobs — often separates economic policy issues and immigration issues. His bid for immigration is based largely in a deeply emotional fear of foreigners that has resonated in his base.

This isn’t about policy, it’s about national identity of white Americans

Between Trump and Breitbart’s worldview it’s clear that immigration as discussed in the Republican Party is no longer a policy issue; it’s about the fear of losing a white national identity.

Trump, leaning heavily on Breitbart’s readership, with the addition of his own bombast, has brought these fears to the fore. Specific policies surrounding immigration have been supplanted by an impassioned appeal to white America.

As my colleagues Dara Lind and Matt Yglesias explained, immigration as presented by Trump and Breitbart is not about the "specific contours of visa programs," it’s about identity politics:

The issue is American identity and American security with threats to the former defined as threats to the latter. Trump’s campaign has proven the potency of this brand of politics in a way that more conventional, more professional politicians have already noticed — see the mainstreaming of anti-refugee politics even while the GOP primary was under way — and will continue to remember in a post-Trump party. The campaign has also served to push the most immigration-sympathetic Republicans out of the party while pulling the most immigration-skeptical Democrats and independents into it with a lasting impact on the balance of power inside both parties. The underlying demographics of the United States are changing in profound ways, and those changes don’t sit well with everybody. For years, those changes were widely discussed in the media but not addressed by the political system. Trump, for better or worse, has articulated fears that research shows have long been present, and it’s worked for him. He may go away, but his key issue won’t.

Framing immigration as an us-against-them debate has worked well for Trump this campaign, as it has developed a readership for Breitbart for even longer. While Breitbart’s CEO Steve Bannon might have an official role in the Trump campaign now, his organization has actively fueled the sentiments behind Trump’s rise long before Trump was even considered a viable candidate to lead the Republican party.

Trumpbart just makes it official.