A month ago, Dr. Dean Winslow, Donald Trump’s choice to serve as the Pentagon’s top health official, was on Capitol Hill yesterday for his confirmation hearing, which seemed to be going well. Then the doctor made the mistake of being candid.

With the mass shooting in a Sutherland Springs church on the minds of many at the time, Sen. Jeanne Shaheen (D-N.H.) asked Winslow about service members convicted of domestic violence charges and whether they should be dishonorably discharged. As part of his answer, the doctor shared his belief that it’s “insane” that “in the United States of America a civilian can go out and buy … a semi-automatic assault rifle like an AR-15, which apparently was the weapon that was used.”

Sen. John McCain (R-Ariz.), the committee’s chairman and a beneficiary of the NRA’s generous support, quickly interjected. “Dr. Winslow, I don’t think that’s in your area of responsibility or expertise,” the Republican said.

Soon after, Winslow’s nomination was put on hold. This week, he wrote an op-ed for the Washington Post explaining that his nomination is now over.

Last week, I withdrew my name from consideration to be assistant secretary of defense for health affairs. My appointment had been put on indefinite hold by the Senate Armed Services Committee, and I felt the Defense Department needed to fill the position without undue delay. Our soldiers, sailors, airmen and Marines deserve the full complement of Pentagon appointees to support them. I am sorry not to be able to assist Defense Secretary Jim Mattis, whom I deeply respect, in building the best and most efficient military health-care system possible. I have the credentials to help, including 35 years of experience in the Air Force (including four deployments to Iraq and two to Afghanistan after 9/11), in military and academic medicine, and in private practice, public hospitals, the Department of Veterans Affairs, the pharmaceutical and diagnostics industries, and public health. But unfortunately, I do not possess one credential the committee wanted to see: I do not support the unrestricted ownership of semiautomatic assault weapons by civilians.

Sen. Chris Murphy (D-Conn.) noted yesterday, “Over the course of his six deployments, Dean L. Winslow wielded weapons of war and saw what they did to the bodies of soldiers. When he said those weapons don’t belong on our streets, his nomination to serve the Dept. of Defense was shut down.”

As we discussed in early November, it’s worth appreciating the fact that if Winslow had been confirmed to the position for which he was qualified, he wouldn’t have been able to affect gun policy in any way. Whether the assistant secretary of Defense for health affairs agrees with the NRA’s agenda or not is ultimately irrelevant in a policymaking sense – because consumer access to weapons of war falls far outside the office’s purview.

But for Republicans, that didn’t matter. Winslow, a Trump nominee, shared the wrong thought out loud. Like much of the country, he thinks it’s “insane” for civilians to be able to buy semi-automatic assault rifles, and in this Congress, it’s a disqualifying sentiment.

“I have no regrets,” Winslow concluded in his op-ed. “Having semiautomatic weapons makes no sense. It is a public-health issue that, as a doctor, I felt compelled to bring to the Senate’s attention. As a citizen, I am saddened that our government has become so dominated by pro-gun lobbyists that an appointment such as mine – which has no responsibility for gun control – can be sidelined by a single sentence of informed, personal opinion. And that really is insane.”