As Israel battles the Hamas terror group following an Oct. 7 assault inside its borders, authorities in the U.S. are urging awareness over the risk of "lone wolf" terror attacks on American soil.
A decade ago, during the rise of the Islamic State group, lone wolf attacks became a shocking new trend that counter-terrorism investigators worked tirelessly to thwart in the U.S. and abroad.
As the Trump administration squashed ISIS overseas, American law enforcement tamped down on the problem at home, leading to a decline in such attacks, according to Paul Mauro, a former NYPD inspector.
ISIS' defeats and the thwarting of domestic terror plots killed the appeal for people who were vulnerable to manipulation under what he called the "loser-to-lion" system, he told Fox News Digital. Lone wolves with nothing going for them believed they could achieve martyrdom through acts of terror, he said.
"You didn’t have to take down the Brooklyn Bridge. You were a lion of Islam if you stabbed your neighbor because he was an apostate," he said.
Last month, FBI Director Christopher Wray told Congress "terror threats have elevated" amid protests and debate over the ongoing war between Israel and the Hamas terror group.
"The reality is that the terrorism threat has been elevated throughout 2023, but the ongoing war in the Middle East has raised the threat of an attack against Americans in the United States to a whole other level," Wray said.
James J. Carafano, a homeland security expert and senior counselor to the president and E.W. Richardson fellow at the Heritage Foundation think tank in Washington, D.C., said the government needs to prioritize law enforcement over politics.
Carafano has studied dozens of homegrown attacks following 9/11, including the Boston Marathon bombing in 2013. He said thwarting them requires following well-established practices of modern policing without political interference.
Both Mauro and Carafano identified two issues that may make Americans less safe — a lack of political unity and the porous southern border.
"Where public safety and national security bump up against politics, the politics win," Carafano said, calling moves weakening law enforcement under the Biden and Obama administrations "deliberate self-weakening."
Under the current administration, he said, the mantra has been that the major domestic threat is violent right-wing extremism, he said.
"That is demonstrably false," he added, but Islamist groups may warrant more scrutiny.
Mauro also said that U.S.-based Hamas sympathizers represent a potential pool for radicalizing future lone wolf attackers.
"You didn’t have this enormous pool of sympathizers with what is a designated terrorist group, Hamas," he said. "That is a legal designation that has nothing to do with where you stand on the Israel-Palestinian conflict."
Multiple lone wolf attacks have already taken place in the U.S. and allied countries, including a woman who allegedly drove into what she incorrectly thought was a Jewish school in Indianapolis last week and a deadly stabbing at a French high school last month.
Long before the war broke out in Israel, however, lone wolves have burst out in violence, including in several high-profile attacks where there may have been missed warning signs.
Trevor Bickford of Maine was 19 when he allegedly drove down to New York City's New Year's Eve celebration and attacked four officers with a machete near Times Square, according to authorities.
He had been under surveillance by counter-terrrorism authorities in the weeks before the attack and had reportedly converted to Islam.
Bickford was accused of crying out "Allahu Akbar!" before slashing one officer in the head from behind and then another officer before police shot him in the shoulder and took him into custody.
According to federal prosecutors, Bickford's plan was to "wage jihad by killing U.S. government officials" and that he had been reading Taliban and al Qaeda propaganda online.
An Islamist husband and wife duo-turned-terrorists attacked a Christmas party in San Bernardino, California, killing 14 people and wounding dozens more. Responding officers killed the husband, Syed Farook, and wife, Tashfeen Malik, in a harrowing shootout.
Authorities later said Malik was an Islamic State group sympathizer who lied on her "fiancée visa" application.
On Oct. 23, 2014, a New York City man rushed four rookie NYPD officers from behind with a hatchet, striking one in the back of the head and nearly killing him and injuring a second before police opened fire and killed the suspect.
Authorities later identified the attacker as Zale Thompson, a Navy veteran who had become radicalized but had no direct ties to any terror groups.
"He had all this jihadi literature, but he didn't appear to be connected to any mosque," Mauro said. "So, where was he getting all this? He was getting this online."
A search of his computer revealed he'd looked up ISIS-related content and the mayor's address. A day before the attack, ISIS posted a video urging supporters to conduct any attacks they could, wherever they could.
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Two brothers from Chechnya planted homemade bombs near the finish line of the Boston Marathon in Masachusetts, killing three and seriously injuring hundreds of people at the crowded event.
Law enforcement and citizens can help stop lone wolf attacks before they happen by remaining alert and reporting suspicious activity, experts say.
"You're going to look for social media activity, radicalization and other behaviors that indicate a particular target of hatred, coupled with a predilection to commit active violence," said David Katz, a former DEA special agent and the CEO of Global Security Inc.
Amid the heightened lone wolf threat and spikes in antisemitism across the country, Katz, a leading gun instructor, has also begun tactical training with a small group of volunteers at his local synagogue in Texas, he said.
"Eleven men and one woman are going to be handling security because we can't trust anybody else to do it, nor can we afford to hire dedicated armed guards," he said.
Fox News' Adam Sabes and The Associated Press contributed to this report.
