Many mass shooters have cited the same racist conspiracy as motivation: the Great Replacement Theory. Now, the theory has found its way into American politics. VICE News breaks down how a dangerous idea moved from the fringes to the mainstream. Help keep VICE News’ fearless reporting free for millions by making a one time or ongoing contribution here. - https://vice.com/contribute Subscribe to VICE News here: http://bit.ly/Subscribe-to-VICE-News Check out VICE News for more: http://vicenews.com/ Follow VICE News here: Facebook: https://www.facebook.com/vicenews Twitter: https://twitter.com/vicenews Tumblr: http://vicenews.tumblr.com/ Instagram: http://instagram.com/vicenews More videos from the VICE network: https://www.fb.com/vicevideo #VICENews #News