The hero National Guard veteran who helped thwart a terror attack on a train in Europe in 2015 gave a dire warning if Daniel Penny is convicted at his manslaughter trial: good Samaritans will be scared to intervene moving forward.

“Do you want people to step up and try to do the right thing or not?” Oregon House Rep.-elect Alek Skarlatos told Fox News.

Skarlatos, an Oregon National Guard vet, and two friends grappled and disarmed Moroccan terrorist Ayoub El Khazzani when he opened fire on a packed Paris-bound train.

He said punishing Penny – a Marine veteran charged in the fatal chokehold death of a homeless man on an NYC subway – would discourage others from protecting people in need.

“If he, God forbid, is convicted, it’s going to frighten a lot of people and blue states into inaction,” he told Fox.

Penny and other witnesses said that Jordan Neely was behaving dangerously and erdically when Penny intervened to stop him.

Prosecutors alleged Penny held on too long and should have known his chokehold could kill Neely. 

Skarlatos said Penny’s trial is the product of a two-tiered state justice system that is motivated by left-wing politics, not serving the people. 

“I think if you live in Oregon, Washington, California and New York, you are kind of concerned that something like this could happen to you, especially if you’re someone who thinks of themself as someone who would step up,” he added. 

“In our terrorist attack, for instance … it happened on a gun-free continent. I wasn’t able to carry. We had to fight this guy by hand,” Skarlatos said, recounting the life-and-death struggle in 2015. 

The fight began when Al Khazzan jumped out of a lavatory on an Amsterdam-to-Paris train wielding an AK-47 rifle, an automatic pistol and a box cutter.

El Khazzan had shot one passenger and slashed another – American Mark Moogalian, who was the first to engage the gunman – before Skarlatos and his childhood friends Spencer Stone and Anthony Sadler grappled him and wrestled the gun away.

“When we kind of got control of him and had him bent over kind of a table in the train car, he was still fighting to get away, and so I just told him, ‘Stop resisting, stop resisting.’ And he didn’t. So I put the handgun to the back of his head and pulled the trigger. And the handgun turned out to be completely empty,” Skarlatos recalled to Fox.

The three were initially afraid to divulge the story to French law enforcement, but FBI agents assured them that “you can do whatever you want to terrorists in France.”

Indeed, the three friends received the French Legion of Honor, the country’s highest avert, for their heroics.

Now, he believes Penny is being nailed to the wall for a similar act of heroism for he protecting a train full of New Yorkers from 30-year-old Needly.

Needly had an active arrest warrant and a history of violence when he began trashing around and screaming about killing people, witnesses say.

Neely also had schizophrenia and synthetic marijuana in his system, and Penny’s defense says the chokehold wasn’t the only factor in his death.

Penny faces up to 15 years in prison if convicted of manslaughter, but there is no minimum sentence, meaning Penny could be given probation instead of jail time.