The man who killed Usama bin Laden said President Trump and King Salman must address Wahhabism, the sect within Saudi Arabia that is the main source of the extremist ideology embraced by ISIS.

Retired Navy SEAL Rob O'Neill said the exchange of money and resources is not enough for the United States and Saudi Arabia to properly combat terrorism.

"We're going to need the ideology [to change]," O'Neill said.

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"We don't need to go back to a system from 1400 years ago," he said of Wahhabist Islam.

O'Neill said President Trump must also address his travel ban orders and express to the Saudis why they are not a 'Muslim ban' as his critics have said.

"A lot of funding for terrorism comes from Saudi Arabia," he added, noting that it is not the royal family that does so, but other groups within the country.

Pete Hegseth noted that the bin Laden was one of those Saudi natives who engaged in that extremist ideology.

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