By Cokie Roberts and Steven V. Roberts

President Trump has declared war on those institutions specifically designed to hold him accountable, legally and politically. The result is a deeply dangerous time for American democracy.

The genius of that democracy can be summed up in three words: checks and balances. The founders feared an unfettered president and designed a complex system of obstacles to limit executive power. Vetoes can be overridden by Congress; regulations can be blocked by federal courts. Presidential actions of all kinds can be investigated by legislative committees, independent journalists and law enforcement agents.

The ultimate barrier against presidential power, of course, is impeachment, but that’s a drastic and inefficient remedy. In most cases, the national interest depends on routine and robust enforcement of one simple principle: that no president is above the law.

That enforcement, however, depends on vital and vigorous institutions capable of standing up to a power-hungry president. And that’s exactly why this president has made such a determined effort to undermine the credibility of those institutions.

His target list ranges from his own intelligence agencies — he called their report documenting Russian meddling in the 2016 election a “tremendous blot on their record” — to his vanquished opponent in that election, Hillary Clinton. Even now, he insists on calling her “Crooked Hillary” and relishes chants of “lock her up” from his most ardent supporters.

But Trump focuses mainly on discrediting the two institutions that pose the greatest threat to his untrammeled power: law enforcement agencies, including the FBI and the special counsel, Robert Mueller; and a free and fearless press. He’s aided and abetted by spineless GOP leaders who refuse to criticize his assaults.

Sen. Jeff Flake of Arizona, liberated by his decision to leave Congress, harshly denounced his fellow Republicans on NBC’s “Meet the Press”: “When the president says things that are just totally wrong, it’s the responsibility of members of Congress, particularly those in the president’s party, to stand up and say, ‘That is not right. Truth is not relative. And there are no alternative facts here.’ … I have seen instances where we haven’t done that well. And we’ve got to do it better.”

The president’s Operation Obfuscation begins with the media. He’s repeatedly called reporters “dishonest,” “corrupt” and “the enemy of the American people,” precisely because they refuse to buckle under his pressure. Just one example: The Washington Post documented that in his first 466 days in office, Trump made 3,001 “false or misleading claims” — an average of 6.5 per day.

Lesley Stahl, the veteran CBS reporter, recently recounted a conversation in which she asked Trump why he incessantly attacked the press. His revealing answer: “You know why I do it? I do it to discredit you all and demean you all, so when you write negative stories about me, no one will believe you.”

Trump’s attacks on law enforcement agencies have the same strategic purpose, to discredit and demean investigators and prosecutors and erode their ability to curb his abuses. His latest disinformation campaign is what he and his allies like to call “Spygate,” the completely unfounded charge that the FBI, under President Obama, planted a spy in the Trump campaign.

In fact, the feds used an informant, a retired professor, to gather evidence of possible connections between the Trump campaign and Moscow. Former CIA Director Michael Hayden called the procedure “stunningly normal” on ABC’s “This Week.” But “normal” has little meaning for this president, who insisted on tweeting that the story, “if true,” amounts to the “all time biggest political scandal.”

The president is “simply trying to delegitimize the Mueller investigation … and he’s willing to throw almost anything against the wall,” said Hayden.

Barbara McQuade, a career federal prosecutor, told The New York Times, “To turn on the FBI using this loaded language like ‘spy’ and ‘infiltrate,’ President Trump is trying to poison public opinion against the FBI for his own reasons.”

Trump’s lawyer, Rudy Giuliani, essentially confirmed on CNN that McQuade is right: Team Trump is trying to “poison public opinion” as a conscious and cynical strategy. “Of course we have to do it in defending the president,” he admitted. “It is for public opinion, because eventually the decision here is going to be, impeach or not impeach.”

The cost here is enormous. In defending himself and deceiving the public, the president is damaging our most basic democratic institutions. And yet, as Flake says, most Republicans bite their tongues even when the president “says things that are just totally wrong.”

Their silence is the real scandal.

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