By Cokie Roberts and Steven V. Roberts

Former Secretary of State Rex Tillerson never denied calling President Trump a “moron” in private. But only after he was fired did Tillerson have the guts to say publicly what he really thought about a president who has no regard for facts.

Speaking at Virginia Military Institute, Tillerson made his target completely clear when he thundered: “If our leaders seek to conceal the truth or we as people become accepting of alternative realities that are no longer grounded in facts, then we as American citizens are on a pathway to relinquishing our freedom.”

Tillerson thus joined a small band of Republicans who have shaken free from Trump’s suffocating influence to publicly state their true feelings about the president. And “moron” is one of their milder accusations.

Some have been liberated by termination. Others, including Sens. Bob Corker and Jeff Flake, shed their inhibitions by deciding not to run again. Sen. John McCain, always a candid Trump critic, has grown even more vociferous in the face of a terminal illness.

There are two lessons to be drawn here. The first is that Trump’s assailants form the small tip of a large iceberg. Corker, who has called the president an “utterly untruthful” person, told The New York Times that the “vast majority” of Republican lawmakers “understand what we’re dealing with here” — namely, a leader who has caused “the debasement of our nation.”

The second lesson is that many of those legislators are cowards, intimidated by Trump’s powerful following within the Republican Party and the president’s well-known capacity for vindictive retaliation.

Rick Wilson, a Republican consultant and persistent Trump foe, told the Los Angeles Times, “The biggest casualty of Donald Trump’s presidency is political courage.”

Rep. Mark Meadows, a Trump loyalist who heads the hardline Freedom Caucus, sarcastically and accurately added, “It’s really easy to be bold when you’re not coming back.”

Still, the truth-tellers are worth listening to. And one of their main criticisms is what Tillerson focused on: Trump’s utter disregard for facts that contradict his world view, an impulse that makes rational policy-making almost impossible.

“We are a mature democracy,” Flake said on the Senate floor. “It is well past time that we stop excusing — or worse, ignoring — these attacks on the truth. For if we compromise the truth for the sake of our politics, we are lost.”

Many Trump critics are deeply worried about his attacks on independent institutions designed to check and balance the president’s power. One of Trump’s favorite targets is the media, and Flake warned, “When a figure in power reflexively calls any press that doesn’t suit him ‘fake news,’ it is that person who should be the figure of suspicion, not the press.”

Rep. Charlie Dent, a Pennsylvania Republican who is also retiring, said Trump has rejected the GOP’s traditional embrace of law enforcement by constantly undermining public confidence in the FBI. “We need to get behind law enforcement, show some respect here, and move away from these conspiracy theories,” he said on MSNBC.

Corker added at a breakfast with reporters: “Continual tearing down of institutions in order to inspire your base and keep yourself protected with your base, to me is damaging to our nation.”

Other renegades charge there are corrupt motives behind some of Trump’s decisions. David Shulkin was axed as Veterans Affairs secretary, he wrote in the Times, because Team Trump “saw me as an obstacle to privatization” of the veterans’ health system “who had to be removed.”

“That is because I am convinced that privatization is a political issue aimed at rewarding select people and companies with profits,” he alleged.

Some of the strongest criticisms focus on Trump’s personality, not his policies. Steve Bannon, once a close adviser, said the president acts “like a 9-year-old.” Corker compared the White House to an “adult day-care center.” Reince Priebus, fired as chief of staff, described the administration’s dysfunction to writer Chris Whipple: “Take everything you’ve heard and multiply it by 50.”

McCain wrote of the president in his new book, “The Restless Wave”: “The appearance of toughness, or reality show facsimile of toughness, seems to matter more than any of our values.”

We owe these truth-tellers a debt of gratitude, even if they are, as Hillary Clinton said of Tillerson, “a tad late.” But where are the others? Why won’t they speak up against an “utterly untruthful” president who has put us “on a pathway to relinquishing our freedom”?

Steve and Cokie Roberts can be contacted at stevecokie@gmail.com.