Transcript for In Europe, some ultra-conservatives say their national identity is at risk
Reporter: This is Poland in 2017. And there are dark clouds descending upon its capital. What was supposed to be a celebration of Poland's Independence day engulfed by tens of thousands of right-wing demonstrators, chanting slurs. Signs reading white Europe, and clean blood. This is what European nationalism looks like. It's angry. It's loud. It's on the rise. Across Europe, this ultra-conservative rhetoric now seeping out of the fringes and into the mainstream. We all know about Europe's dark history of hate. Following the migration crisis there's been a resurgence in right-wing thought. This is the culture we have in Europe, we don't have a Islam culture here. Nationalists getting back into mainstream politics. From the streets of Germany. To packed stadiums in France. Battling to regain what they say their countries are losing. Their traditional identity, their culture, their heritage. Yesterday that message amplified with a click of a button. This time in the United States. When president trump tweeted a string of inflammatory videos purporting to show violence being committed by muslims. President president, why have you been retweeting anti-muslim videos? Reporter: The videos shared by an anti-islam ultra-nationalist party Britain first, a group known for hate-filled incitement. Jay defranzen, the group's deputy leader, thanked the president. How delighted I am that as the leader of the free world you took the time to retweet three of my videos. Donald Trump retweeted three of my tweets because he wanted to raise awareness on issues regarding immigration and lack of border control. Reporter: Condemnation came swiftly from Britain's highest office. Britain first is a hateful organization. Reporter: A rare rebuke from the country's closest ally. Franzen argues her movement is based not on hate but on the feelings of ordinary citizens. You're seeing a side of politics that has actually been on the back foot for a long time, and that is the patriarchy, commonsense, everyday man saying, if you live in the uk, I should be put first before immigrants. Reporter: The attacker was not a migrant after all. The embassy in the Netherlands saying the attacker was Dutch tweeting to the president, fact dozen matter. Yet the white house doubled down denying the president was pushing anti-muslim propaganda. It doesn't matter if the video is fake? I'm not talking about the nature of the video, I think you're focusing on the wrong thing. Reporter: Making a case for national security. The threat is real, that's what the president is talking about. Is the need for national security, the need for military spending, and those are very real things. There's nothing fake about that. Reporter: This is a refrain that echoed throughout our trip across Europe. We're on our way to graz in southern Austria, a part of the country which has quite a long history of right-wing extremism. Today porous borders and changing DEM graphics seem to be reviving some of those views. Stop immigration fast and to keep going to reimmigration. Because I think it's one of the most important things now. Reimmigration? Reimmigration, yes. What does that mean. To bring the people back. To give them motivation to back to back to their countries. He was quit to point out what he says led to his black eye. I was in an attack from muslims. We stand on the street and they attacked us from behind. There was no reason before. You're saying muslims attacked you? Yeah. Reporter: Since he didn't go to the police there's no way to substantiate this claim. To spread their ideas beyond their circle, he says there are 300 members in Austria. The group organizes public stunts like this one. One of the most important principles in our movement is to make actions but peaceful. Provoke but be peaceful. Reporter: Papier-mache dolls on the steps of the green party headquarters. It wasn't a huge event but I think the point is they documented it and they're going to share on it social media with all the other groups like them across Europe. The point of this is it's kind of building up a fraternity of nationalists, if you like. Each of them protesting for what they believe is European culture in peril. He insists his views are not bigoted. I don't have a feeling of supremacy because I'm white. Christians and muslims have the same god. They just beat each other in my belief is the better one sort of thing. I think for people watching at home, I think they might think that the logic starts to run out when you say that you don't think that your culture is better, but they should leave. It's my own culture. It's the culture of my parents, of my uncles. And we have a duty to keep going on. Reporter: Next we head to Hungary. One of the oldest countries in Europe. Two years ago, one of the landmarks here became an icon of the refugee crisis. This is the kaleti train station. It was here thousands of migrants and refugees from north Africa and parts of the middle East were stopped from making their way further into Europe. Pictures of people crammed onto trains and waiting outside made headlines around the world. I think it was those pictures that really criticalized the idea amongst the far right and their supporters that Europe was somehow under attack. These images bolstering the right wing party already in office, the country becoming a de facto base for right-wing thinkers from across Europe. What we're discovering is there's kind of two groups in this kind of right-wing movement in Europe. There's the kind of young guys, young activists that we met in Austria. There are the bigger players, the bigger thinkers if you like. One of them is Daniel Freeberg. He partnered with Richard Spencer, the self-proclaimed white nationalist. Now one of the most recognizable faces of the so-called American alt-right movement. Hail our people, hail victory! Reporter: He was propelled to the national spotlight after this video showing his audience throwing the Nazi salute went viral. You will not replace us! Reporter: And Freeberg in attendance at the charlottesville rally. It's basically a global phenomenon. The American alt-right inspired by the new right from France and Germany and Belgium especially. Movements all across Europe. Reporter: Friburg has long been a leading figure of the Swedish right, said to be the world's largest distributor of far-right literature. Tell me what you believe to be wrong currently with western politics. Everything. Rather obviously mass migration. The great replacements. Which are what we're experiencing in Europe today. You feel like you're being replaced by? I don't feel like it, I know that we are. Because I know how to read statistics. People of child-bearing age, 47% of this segment are already noneuropean in Sweden. If that is not replacement, I don't know what is. Reporter: Friburg claims there's one important difference between the nationalist movements in the usa and Europe. In Europe we don't use the term white for obvious reasons. That's not the people's primary identity. People identify as a Swede. In the states they talk about white. White people. For a good reason. Because white and black in the U.S. Is -- are kind of household words. The ethnic background of being white is the thing that differentiates people from, say, immigrants and refugees and asylum seekers that -- Yeah, but we use the word European. And noneuropeans. Because that makes more sense for us. Reporter: But Joe muhall, a senior researcher from the British hope not hate campaign, says the immigration argument is masking the real message. They think that's a message that will sell and that will work. Perhaps they're correct. There's high levels of concern around those issues in Europe. We have to look at what they're talking about. Being there speaking to these young people, a lot of them say, we're not fascists, this is not a Nazi movement, this is not classical right wing. This is just about migrants and our identity. Isn't that just an argument? We have to have discussions about the levels of immigration, et cetera. What we're seeing is fundamentally different to that, their ideas fundamentally rooted in European fascist thought, they're racist, islamophobic, often anti-semitic, homophobic. There's a whole package that goes well beyond saying it's just about the levels of immigration. Reporter: Back in Poland, on streets where the scars of a war waged by fascists still run deep, hints of those sentiments reemerging. An interesting display of books here. This one called "Homo terror." The other one I think is about the jewish lobby in Poland. Literature you'd normally see outside of church? What this is one about? Homo terror. Homo terror? Reporter: On this day there aren't crowds clamoring for these books. And despite the strong showing at this Independence day rally, these demonstrators remain in the minority. For now. Yet with every chant, every footstep, and every tweet, their message is growing louder. For "Nightline," I'm James Longman in Warsaw. Next, Matt Lauer making his
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