The Shamsud-Din Jabbar New Year’s massacre in New Orleans, carried out with an ISIS-flagged pickup truck, could embolden the terrorist organization to radicalize more Americans, experts told Fox News Digital.

Jabbar’s younger brother told The New York Times that he and his brother, an Army veteran, were raised Christian in Beaumont, Texas, before the now-deceased attacker converted to Islam as an adult.

“What he did does not represent Islam,” the younger brother said. “This is more of a kind of radicalization, not a religion.”

SUSPICIOUS TRUCK ATTACK IN NEW ORLEANS INSPIRED BY ISLAMIC STATE TERRORIST GROUP

Shamsud-Din Jabbar, a suspect in the New Orleans attack, is seen in this social media image posted in November 2013 at Fort Johnson (formerly Fort Polk), Louisiana. (1st Brigade Combat Team, 82nd Airborne Division via Facebook via Reuters)

He added that Jabbar didn’t know what he wanted to do in life and began his military career “to gain some kind of discipline.”

While traveling from his home in Texas to Louisiana on Tuesday, Jabbar posted videos on his Facebook account pledging his allegiance to ISIS, law enforcement sources said.

Retired FBI agents Scott Duffey and Chris Swecker told Fox News Digital that Wednesday’s attack could embolden ISIS, other terrorist groups or radicalized individuals.

New Orleans terror suspect’s brother says attack was a sign of ‘radicalization’: report

ATF agents are investigating a New Orleans rental home used by Shamsud-Din Jabbar on Thursday. (Kat Ramirez for Fox News Digital)

“This is a time when ISIS is under extreme stress and its existence in Syria and elsewhere is threatened. It would make sense for them to double down on their message to radicalize Americans to put it into action and activate every cell they have in place,” Swecker said.

Before his rampage in New Orleans, Jabbar posted several videos on Facebook expressing support for ISIS, the FBI said at a news conference Thursday.

“In the first video, Jabbar explains that he only intended to harm his family and friends, but he feared that the headlines would not focus on the ‘war between believers and unbelievers’.” FBI Deputy Director Christopher Raia said.

ISIS and other terrorist organizations often use social media to recruit new members, experts say.

NEW ORLEANS ATTACK: The investigation continues as the FBI says there are no other suspects involved

“ISIS and other foreign adversaries use all possible social media platforms to spread anti-American ideologies, rhetoric and propaganda,” Duffey said. “It is free speech and is intended to slowly make young people question their American and religious ideals.”

“It starts with soft messaging to engage people in their thought process,” he added. “Links are often provided that lead people to further messages… sowing division and distrust of government in young, impressionable minds.”

“I think that there is often an underlying mental problem in the reader that draws them to the message, which over time leads to… even more coded messages of violence.”

“For them, it’s a win when someone does something like they did yesterday.”

Investigators searched a New Orleans rental home used by Shamsud-Din Jabbar on Thursday. (Kat Ramirez for Fox News Digital)

Most people are radicalized by online materials, said John Ryan, who served as chief of the Port Authority of New York and the New Jersey Police Department.

“Since he’s an IT professional, that would mean he probably knows how to access the dark web, where there’s a lot more material available,” Ryan said of Jabbar’s background in information technology.

“As far as whether it might trigger other people, unfortunately there are a lot of keyboard warriors who face it and are looking for something to connect with. Given the high levels of mental health issues in the wake of COVID and the number of protests in support of Hamas and pro-Palestine and anti-Israel people, the answer is yes.

Although law enforcement officials initially searched for accomplices in the attack, the FBI said Thursday that it appeared Jabbar acted alone. However, according to Swecker, this does not rule out the possibility of an active terrorist cell in the country.

“If his radicalization is due to IS propaganda and calls on the Internet, it is (still) international terrorism. We call him a domestic terrorist, but he comes from a terrorist organization,” Swecker said.

“Even if he doesn’t carry a card, even if he doesn’t talk to the ISIS director on the phone but calls to action through propaganda on their websites, it’s still international terrorism,” he said. “This is a key part of the plan for al-Qaeda and these international groups.”

Jabbar was stationed at Fort Bragg, now Fort Liberty, in North Carolina, as was active-duty U.S. Army soldier Matthew Livelsberger, who police said was killed in an explosion outside the Trump International Hotel in Las Vegas on Wednesday that killed seven people were injured, used intentionally and died.

Despite the suspects’ shared military history, investigators have found no evidence linking the Bourbon Street terrorist attack in New Orleans to the Cybertruck explosion in Las Vegas.

The driver of the Tesla Cybertruck that exploded outside the Trump International Hotel in Las Vegas on New Year’s Day has been identified as active duty U.S. Army soldier Matthew Livelsberger (pictured right). Livelsberger’s attack occurred just hours after Jabbar’s in New Orleans. (Fox News)

“If they served on the same base, I think it’s still very open and there’s a distinct possibility that they connected over the Internet or with their former military associations,” Swecker said. “If (Livelsberger) had been a convert, he would have attended the same (religious) services as (Jabbar).

CLICK HERE TO GET THE FOX NEWS APP

“What (Jabbar) did and what happened in Las Vegas gives credibility to the movement and creates that excitement among others who may be thinking about implementing (continuing) their plan in a short period of time,” Duffey said.