Mark R. Warner, a Democrat, represents Virginia in the U.S. Senate and is vice chairman of the Senate Intelligence Committee.

In the world of national security, what we don’t know can hurt us. The men and women of the intelligence community work every day against that unknown, searching for the truth — uncovering our enemies’ secrets to help keep Americans safe.

Presidents do not always agree with the intelligence community’s recommendations, and that independence can be good. But the role of U.S. intelligence services is, and must be, to speak truth to power, even when it is not politically convenient.

Over the past three years, President Trump has made no secret of his distaste for the intelligence community’s independence, which is fundamental to its proper functioning. As vice chairman of the Senate Intelligence Committee, I have been deeply disturbed watching the president disparage the work of these brave Americans and publicly cast doubt on intelligence findings that run counter to his political narrative. But some of the president’s actions are more worrying than his words or tweets, and I have been particularly troubled by the politically motivated firing of senior intelligence leaders. These firings threaten to do lasting damage to the intelligence community.

Late on a Friday night this month, in the midst of a global pandemic, the president fired the intelligence community’s inspector general, Michael Atkinson. It’s clear that Atkinson was not targeted because he had failed in his job as the intelligence community’s chief watchdog or because he had broken a law. No, Atkinson was fired precisely because he did his job and followed the law requiring him to alert Congress about a whistleblower complaint, a report that later led to the president’s impeachment hearings.

This firing adds Atkinson to the disturbing number of intelligence officials who have been pushed out by this president — a list that includes two directors of national Intelligence, multiple well-regarded career intelligence officials, and the acting director of the National Counterterrorism Center.

What each of these ousted intelligence officials has in common, besides a history of service to our country, is that all were punished for speaking truth to power. They were fired because they had the temerity to brief the president and Congress about threats to the United States that are politically inconvenient to Trump.

In the case of the most recent director of national intelligence, Joseph Maguire, his offense was permitting the House Permanent Select Committee on Intelligence to be briefed about Russia’s efforts to interfere in the 2020 election. And Maguire’s predecessor, Daniel Coats, was, according to media accounts, forced to step down because he provided assessments on Russia and North Korea, among other matters, that angered the president.

Already, the consequences of this remaking of the intelligence community in Trump’s image are visible. Senior intelligence officials are increasingly reluctant to engage in otherwise routine, nonpartisan communication with the congressional committees that oversee the intelligence agencies, for fear that something they say in a hearing or briefing will anger the president. At a more basic level, the Office of the Director of National Intelligence lacks a single Senate-confirmed official. For now, this crucial office is headed by a temporary appointee and career political operative with little experience in intelligence and few obvious qualifications beyond political loyalty to the president.

These actions send profoundly dangerous signals to career intelligence professionals. If presenting objective information about threats to the United States is treated as political disloyalty to the president, our intelligence community simply cannot function as it was intended to. The consequences of this breakdown will undoubtedly be measured in American lives.

The intelligence community is far from perfect. It makes mistakes. As vice chairman of the Senate committee overseeing our nation’s intelligence agencies, I often see the worst consequences of those screw-ups. But I also see the best our intelligence community has to offer. And that best is made up of professional men and women who work hard every day gathering objective information about what the bad guys of the world are doing to harm our country, and what we can do to stop them.

Their objectivity and the credibility it gives them are our first line of defense. Efforts by this president to intimidate and extract personal loyalty from U.S. intelligence services may be politically advantageous in the short term, but over time the consequences for our country will be disastrous.

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