After a Saudi pilot opened fire on U.S. military personnel in Naval Air Station Pensacola last week, killing three, the Pentagon has ordered a halt to bringing in any new international military students until a more thorough screening process can be implemented. According to Pentagon Spokesman Jonathan Hoffman, no formal ban has been put into place, but no new students will be allowed entry into the nation until the necessary changes have been made.

“If something else were to happen and we had not taken steps to address and enhance our vetting and screening, that would be unacceptable to the American people and we should be held to account for that,” Hoffman said.

Last week’s shooting saw Saudi Air Force 2nd Lt. Mohammed Alshamrani, 21, open fire in the naval base where he was a student, killing three and injuring ten others. Investigators have yet to definitively say whether or not Alshamrani acted alone, but about a dozen of his fellow Saudi students remain confined to the base amid the ongoing investigation. The FBI has stated that until evidence arises that supports a different supposition, the incident is being investigated as a terror attack. Alshamrani died after a shootout with the sheriff’s deputies.

The investigation that followed suggests that the Saudi national had been radicalized as far back as 2015. This begs some hard questions about the vetting process for foreign students aboard U.S. military installations. He also apparently had an interpersonal conflict with an instructor at the school that led him to file a formal complaint after being referred to in class as “porn stache.” Alshamrani was able to legally acquire a Glock handgun after getting his hunting license in the state of Florida — a loophole that even surprised Florida’s governor.

“The Second Amendment applies so that we, the American people, can keep and bear arms,” Florida’s Republican governor, Ron DeSantis said. “It does not apply to Saudi Arabians.”

Despite his apparent radicalization and issues with name-calling, little has been uncovered thus far regarding the Saudi 2nd Lieutenant’s motive. According to the SITE Intelligence Group, Alshamrani had published posts on Twitter and other social media platforms that seemed to echo talking points previously championed by now-dead Al Qaeda leader Osama Bin Laden. Alshamrani’s Twitter account has since been suspended. Classmates noted that upon his return to the United States from Saudi Arabia in February, he seemed to have become “more religious,” prompting some to wonder if something occurred during his recent trip home that spurred the eventual attack.

There are currently some 5,000 students from 153 different countries enrolled in U.S.-based military training programs ranging from electronics repair to advanced counter-terror operations. These programs have long been seen as a means to foster interoperability and friendly relations with allied nations. But now some lawmakers have begun calling these programs into question. Recent reports suggest that there’s little in the way of oversight into these programs, and it’s unclear just what quantifiable benefit they actually provide. There are even a number of accusations that U.S. trained foreign military personnel have gone on to commit war crimes in their home nations, aided by the skills they developed in the United States.

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However, even the father of one of Alshamrani’s victims has spoken out in support of these foreign education programs. Sameh Haitham, whose 19-year-old son, Airman Mohammed Haitham, was killed last week, pointed to the fact that he too is an immigrant, and recognizes that not all Saudis share the gunman’s twisted view of the world.

“I think it’s a great opportunity to train here in the U.S., in order to go back and defeat terrorists in their countries,” Mr. Haitham said. “But we must be very, very careful on who’s allowed to come in.”