Elbridge Colby, the nominee to be undersecretary of defense for policy, said during a 2012 event that the consequences of attacking Iran to destroy its nuclear program would be worse than Iran acquiring nuclear weapons, in video that has been circulating among members of the Senate Armed Services Committee ahead of his confirmation hearing on Tuesday.

“The only thing worse than the prospect of an Iran armed with nuclear weapons would be consequences of using force to try to stop them,” Colby, who was an analyst at the Center for a New American Security think tank, said in the resurfaced video clip.

Colby’s past views on Iran, including his belief that the U.S. can contain Iran and stop it from using a nuclear weapon if it were to obtain one, could be a sticking point for some skeptical Senate Republicans at his confirmation hearing if Colby sticks to those views.

Most U.S. lawmakers on both sides of the aisle have seen an Iranian nuclear weapon as a red line.

“The key bottom line is to show Tehran that they will not gain from nuclear weapons acquisition, but that they will suffer from the attempt to use it,” Colby said during the event on the prospect of containment. “Basically to put a kind of crude way of putting it, the idea is to put our foot on their neck so that they can’t really gain from the acquisition.”

A spokesperson for Colby did not respond to a request for comment.

Elsewhere in the debate from which the clip is excerpted, Colby argued that a strike on Iran’s nuclear program would only delay the program slightly, lead Iran to more aggressively pursue nuclear weapons and lead the Iranian people to rally around the regime; involve significant costs to the U.S. and Israel; and alienate the international community and incentivize other countries to pursue nuclear weapons. 

He also said that “containment and deterrence is tough, it’s not a great option, but it’s doable.”

Prior to that, in 2009, when Colby was a member of the Strategic Posture Commission, he wrote that — in the event Iran acquires a nuclear weapon — the U.S. could “seek to ‘educate’ Iran concerning the limited value of nuclear arms for compliance and other offensive strategic objectives” and “towards ‘normal’ nuclear status” and potentially offer the regime advice to “minimize the likelihood of inadvertent loss or use.”

The comments predate the original Obama-era nuclear deal with Iran in 2015.

Donald Trump Jr., a prominent Colby backer, insisted in a February op-ed that “Colby is also fully in line with my father on the issue of Iran. Colby has repeatedly said he opposes a nuclear-armed Iran, and fully supports my father’s policy to prevent that.”

Trump issued an executive order re-implementing maximum pressure sanctions on Iran, but has repeatedly expressed interest in a new nuclear deal with the regime.

Meanwhile, a group of conservative national security officials, led by former National Security Advisor Robert O’Brien, is circulating an open letter to senators in support of Colby.

“Mr. Colby is a dedicated patriot, a distinguished leader and a strategic thinker. He has consistently demonstrated exceptional expertise, dedication, and vision throughout his impressive professional career in service to the public and our national interest,” the letter reads. “His dedication to advancing U.S. national security interests and his ability to navigate complex challenges with foresight and precision are qualities that set him apart as a nominee for this post.”

O’Brien did not respond to a request for comment.