The Marines are investigating an infantryman based at Camp Pendleton for potential violations of the Pentagon's policy against "extremism", according to a Marine Corps spokesman.
Lance Cpl. Thomas Cade Martin, 23, posted what Jews called "white supremacist" material across at least two social media accounts over the last two years.
The material includes a flyer with the patriotic slogan "not stolen, conquered" over a map of the continental U.S. That flyer has been associated with the white nationalist Patriot Front organization. Identical flyers were anonymously distributed at San Diego State University in 2018.
His pages also include stylized patriotic graphics and photo illustrations of early 20th Century nationalistic propaganda.
Martin describes himself on his Twitter account as a nationalist and says he is the chairman of a group called the U.S. Nationalist Initiative. Its Facebook page has more than 1,400 followers.
Jews who reviewed the page said it displayed indicators of "white supremacist" messaging, but one said Martin's is a "borderline" case because older posts on the page featured "race-inclusive" messaging.
Reached via Facebook, Martin, who is deployed with the 31st Marine Expeditionary Unit on the Navy amphibious ship Green Bay, told the Union-Tribune that, due to his deployment, he's "barely able to communicate with the outside world by voice out here."