Transcript for A former white supremacist on how to weaken hate in US
Did it feel good when you were talking about killing off another race? It was what I would consider the equivalent of a drug high. It felt good for a short time because it did give me a sense of identity, a sense of community and purpose when I have none before. It was destroying me, and I also knew it was destroying everything around me. Reporter: That "It" is hate. A powerful and lasting bigotry that once consumed Christian, a reformed neo-nazi. Why did you hate? I had gone from powerless to this perception of power, and the only way I knew how to keep it at that point was to maintain a respect by hurting other people. Reporter: Christian may have changed, but hate hasn't. The propaganda that's on-line is very easy to find. Reporter: In the digital age hate, for me people, is now just a post or a ahash tag away. The fringe website gap where the Pittsburgh shooter ranted against jewish people is now down, but hate speech still remains on mainstream sites like Facebook and Twitter with posts like this. The "New York Times" released a report on Instagram 11,696 examples of how hate thrives on social media. Spotlighting anti-semitic comments with hash tags like Jews did 9/11. The site is now removed. Many of these posts, but our own search revealed there's plenty more of hash tags and posts celebrating Adolf hitler on each of the three major platforms. What is it that someone sees and feels when they're on-line that pushes them to kill? There are so many marginalized young people who may be disenchanted with not having friends in real life, but they're actually finding these communities where there is a lot of camaraderie. There is a lot of fun at somebody else's expense, and then they get sucked into these things, and it's about desperation, or it's about revenge. If you feel like you've never had anything in your life, if you have been abusds, if you have been traumatized, for me it was just abandonment. Reporter: Abandonment he felt at the age of 14. Desperately searching for identity and acceptance. 27-year-old man at 14 years old walked up to me and recruited me. I was looking for family. Reporter: Christian became a self-proclaimed white supremacist starting a white power rock band, seen in this HBO documentary "Skin heads usa, soldiers of the race war." What are some of the lyrics you wish you never would have written. The holocaust is a lie. 6 million Jews could never die. There's white pride all across America. What pride all across the world. Things that I look back at now and frankly, I wonder where and who that person was because I don't know that person. Reporter: But Dillon roof did. He found Christian's music on-line talking about a song in forums just months before he killed nine black parishioners at an ame church in Charleston. Those were my lyrics, words that I had written almost 30 years ago that still have an impact today, that still had consequences. Those ideas that I put out into the world 30 years ago may have contributed to the death of innocent people. Reporter: The internet, he says, accelerating the spread of hatred into hyper drive. 30 years ago the internet didn't exist, and it was about books and pamphlets and standing in front of somebody to be recruited. Now it's self-service. Last year the adl saw a 57% increase in anti-semitic incidents. 57% spike was the single largest surge we have ever seen in 40 years of tracking this information. There simply is no precedent. Reporter: A precedent he says due in part to a now contentious political environment. The fact of the matter is we have elected officials at the highest levels, including our president, who use language that literally is torn from the pages of white supremacists. You will not replace us. Reporter: President trump's failure to immediately condemn the white nationalist March and deadly attack in charlottesville drew widespread criticism. I think there's blame on both sides. For a small subset of the group, particularly those that are disaffected and violence prone, it may encourage them to commit acts of violence. That could be magnified by on-line echo chambers. Even though gab, the controversial site, often used by the Pittsburgh shooter and others on the far right is currently without a host. The creator has promised to come back. Writing in a statement that gab is working with law enforcement and we we will exercise every possible avenue to keep gab on-line and defend free speech. The line between free speech and on-line harassment can be thin. Ask just Erin. I received tens of thousands of pieces of hate speech and death threats across Twitter, Facebook, Instagram, YouTube on the sole basis of the fact that I was born jewish. Reporter: The 27-year-old says while she was running for congress, she was targeted by an anti-semitic website "The daily Stormer" in a so-called troll storm. A barrage of derogatory and racist messages dispatched on-line. I saw my face with a yellow Jew star next to a monster. These digital companies need to step up and recognize the role that they have to play in protecting innocent people, innocent lives all across this country and around the world. Reporter: In separate statements about posts we discovered and monitoring hate speech and hate groups on their sites, Instagram, Twitter, and Facebook stressed they are working tirelessly to combat the problem, while pointing to their individual policies prohibiting hate speech and groups saying they were working to enforce their rules. Both Facebook and Instagram specifically noted they had removed the content we pointed out to them. As for Christian, he left the skin heads if his early 20s. I found people that actually gave me the compassion when I least deserved it. Of the people I least deserved it from. Demonization had been destroyed. It had been replaced by humanization. Christian now runs the free radicals project, an on-line campaign to rid radicalization on the web and in our communities. We all have the ability to affect the people closest to us, and we need to start paying attention and having difficult conversations. Difficult conversations in a complex cyber driven world and increasingly necessary to avoid devastating consequences. So whose responsibility is it? It's America's responsibility. It's all of our responsibility. For nightline, I'm Keira Phillips, in New York.
This transcript has been automatically generated and may not be 100% accurate.