Mike Cerre: Nearly half of the veterans charged in the Capitol siege were former Marines, despite their having served in the country’s smallest military branch.

Lloyd Austin, Secretary of Defense: It's not new to our country and sadly, it's not new to our military. What is new is the speed and the pervasiveness with which extremist ideology can spread today.

Navy Capt: The stand down you're experiencing today is the Navy swarming against this threat.

Mike Cerre: In response to the Capitol riot, Secretary of Defense Lloyd Austin ordered all  U.S. military units around the world to stand down from their normal operations to address the domestic extremism threat.

Capt. Alex Newham:  The reason we're doing this training is first to define it, why we're doing it, what's the cause of it and how to prevent it.

1st Sgt. Joey Cruz: So if you see someone putting something that's extremist out there, as a fellow Marine, it's now your duty to report it.

Mike Cerre: Marine Company Commander Captain Alex Newham and 1st Sgt. Joey Cruz, the company’s senior enlisted man, were tasked with conducting the extremism training and reviewing the Marine corps’ regulations with their unit Fox Company 2nd battalion, 5^th Marines at Camp Pendleton, California.   

I first connected with Fox 2/5, also known  as “the Blackhearts”, while embedded with the unit during the Iraq War, when the focus was more on defending against foreign, rather than domestic threats to the Constitution as part of their enlistment oath.

Sgt. Radcliffe Humphrey, Squad Leader: Support and defend the Constitution against all enemies, foreign and domestic. I mean, you already took the oath. I think the problem is not fully understanding what you signed up for. 

Mike Cerre: Sgt. Radcliffe Humphrey and three of his Fox 2/5 colleagues agreed to share their understandings of the domestic extremism threat within the military and their rights and responsibilities as Marines after their stand down training session. 

It included running through various scenarios and identifying possible extremist intrusions within their ranks.

Mike Cerre: How many of you know what Pepe the Frog stands for? Or “88”? 

Staff Sgt. Rees: I do. Pepe the Fog was just the internet meme that they utilized. You know, I think like the Proud Boys utilized Pepe the Frog memes to make dog whistle jokes towards the Left and “88” would stand for “HH” Heil Hitler and other right-wing connotations. 

Mike Cerre: Most of the training was based on the Pentagon’s prepared outline of do’s and don’ts, as they apply to service members’  political activities and sharing extremist posts on social media.

Cpl. Noah Martin: You could report it and or just not respond to it.

Sgt. Radcliffe Humphrey: Then whoever's posting that, obviously you can just be like, all right, I want to distance myself from this. Get rid of whoever's profile that is, delete them as a friend, delete them as a follower or whatever you have them as, get rid of them from your social media. 

Mike Cerre: Generally speaking, service members are allowed to have political opinions, but they’re restricted from promoting them while serving. 

Sgt. Radcliffe Humphrey: I'd be defacing the Marine Corps as a whole if I said my political beliefs because it's not everyone's. My political beliefs aren't the same as these gentleman's political beliefs. They're going to be different just like anyone else’s would be. 

Mike Cerre: Is it clear in your mind what extremism is? I mean, you know, one man's extremist could be another man's patriot. 

Lance CPL Nicholas Jones, Squad Leader: I mean, in this day and age, I would say that it could be hard for some. But again, it goes back to the training that we're receiving now. 

Mike Cerre: The new directives on extremism prohibit identifying with extremist organizations, displaying their symbols like tattoos and bumper stickers, demonstrating on their behalf in or out of uniform, promoting any illegal activity or messaging, especially on social media.

Given the sensitivity today and the training you went through, if a Confederate flag was spotted in your barracks or in your group, what would be done? 

Staff Sgt. Rees: Oh, yeah, they're going to be held fully accountable for their actions. They know they know what it stands for. They understand why they're putting it up. There's not going to be a question about that. And so they're going to-- they're going to face “the man” and answer for it. 

Mike Cerre: There is always going to be a lot of grey in this. It’s not going to be totally black and white. So what’s the “commander’s intent” here, if  in doubt how do you think they’ll make the right call?

Capt. Alex Newham: So the commander's intent is that they are all informed of the training and everyone has the knowledge that they have. They have the skill sets now. But honestly, the meat and potatoes is going to be from the squad leaders and the team leaders doing the small group discussions because we can't be everywhere all at once. 

Mike Cerre:  Given the intensity of their profession and interpersonal relationships, there is very little room in the Marine Corps for doubts over someone’s loyalty and allegiance.

Drill Instructor: You’re now onboard Marine Corps Recruit Depot  Parris Island, South Carolina.

Mike Cerre:  From Day One of getting off the bus at Marine boot camp, standing on the yellow footprints, giving up their personal items and getting heads shaved. Marines knew they were giving up  much of their personal identities  to become part of something larger than themselves .

Cpl Noah Martin: What it means to me is that you're being shaved from like your civilian life and you're joining this institution and you're going to uphold these standards. 

Mike Cerre: And on that same day when you were on the yellow footprints and they were saying, there's no black, there's no white, there's only green  

Cpl Noah Martin: Roo-rah.

Mike Cerre: Does it stick? Does it stand this test today?

Cpl Noah Martin:  It does.

Lance CPL Nicholas Jones: Absolutely.

Staff Sgt. Rees: You're getting a whole new set of core values of honor, courage and commitment. So it's pretty easy, you know, just as long as you follow those rules and you uphold the life value and you take care of your brother on your left and right and you uphold the Constitution of the United States, like you promised you would, there’s not going to be any issues. 

Mike Cerre, Camp Pendleton, CA: Semper Fidelis: always faithful. That’s how Marines address each other. It’s also key to the Marines Corps strategy for keeping extremism out of its ranks by keeping the focus on the bonds and allegiance that drew men and women to the Marine Corps in the first place.

Cpl Noah Martin: I would say that there's extremism, but with the training that we're getting today and with the training that will be pushed out. I think it could be mitigated

Sgt. Radcliffe Humphrey: The Marine Corps isn't harboring or taking in extremists left and right out of America.  I would say it's pretty on par with the rest of the country. We're people too, you know, we're going to have onesies and twosies outliers from the baseline who are extremists.

1st Sgt. Joey Cruz: Everything that goes on out in society can definitely impact our service members. The difference is that if we continue to equip them and train them and educate them. They’ll understand it a little better. 

Sgt. Radcliffe Humphrey: The reason why that's so important is because especially in our profession as infantrymen, we have to be able to look to our guys left and right and say, I know if we go to combat, this guy's gonna have my back no matter what happens.

Mike Cerre:  For the PBS NewsHour, this is Mike Cerre  reporting from Camp Pendleton, California.

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