Frank Wuco, a former conservative radio host and naval intelligence officer, has also promoted far-right conspiracy theories, such as debunked claims that Barack Obama was not born in the United States.
“I don’t think it’s been our policy really to just start nuking countries,” he replied.
“I think if we were going to have done that, my preference would have been to have dropped a couple of low-yield tactical nuclear weapons over Afghanistan the day after 9/11 to send a definite message to the world that they had screwed up in a big way.”
Mr Trump has repeatedly claimed he could win a war in Afghanistan in a week without using nuclear weapons but said he would not do it because he is “not looking to kill 10 million people”.
However, the president has not provided any evidence for how he could bring an end to the conflict, which has lasted for more than 18 years.
A recent tweet by the State Department referred to Mr Wuco as a senior adviser in the Bureau of Arms Control, Verification and Compliance (AVC).
He previously came under scrutiny last year, when recordings of him promoting several far-right conspiracy theories were reported by CNN.
In those recordings, Mr Wuco complained about the “Zimbabwe-fication” of America and promoted an unfounded theory that a top Hillary Clinton aide had ties to the Muslim Brotherhood, an Islamist political group, and the unfounded claim that former CIA director John Brennan converted to Islam while he was in Saudi Arabia.
At the time, Mr Wuco was working as a senior adviser at the Department of Homeland Security (DHS), leading a team tasked with enforcing Mr Trump’s travel ban, according to CNN.
A spokesperson for the department said his past comments had “no bearing on his ability to perform his job for the American people.”
It is unclear when exactly Mr Wuco transitioned to the State Department from DHS.
The State Department has not yet responded to a request for comment on Mr Wuco’s new role.
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