Barack Obama urged Americans to resist President Donald Trump’s bullying. Joe Biden warned that Trump is wrecking the “sacred promise” of Social Security. Bill Clinton decried the emphasis on grievances and the need to dominate.

In an extraordinary stretch of just over two weeks, three former presidents have taken to the public stage to sound the alarm against the current occupant of the White House, despite the tradition that former presidents generally refrain from publicly criticizing their successors.

Obama, Biden and Clinton did not explicitly name Trump, but their message was unmistakable. The three Democrats said, as much by their presence as their words, that these are unusual times for American democracy, that norms are being disregarded and extraordinary measures are required. The only living president who has not spoken out since Inauguration Day is Republican George W. Bush, though he has made little secret of his antipathy for Trump.

“Former presidents are uniquely qualified and situated to raise their voices and warn the American people if the country is taking a dangerous turn,” said Timothy Naftali, a historian at Columbia University’s School of International and Public Affairs. “Think of them as a sort of advisory council to the people of the United States. And when the advisory council sounds the alarm, the people should listen.”

The ex-presidents made their statements in settings that underlined their points and their alarm.

Obama spoke on April 3 at Hamilton College in Upstate New York, one of the country’s oldest colleges, pushing back against Trump’s pursuit of universities and other institutions and urging those with resources to fight back.

“It is up to all of us to fix this,” Obama said. “It’s not going to be because somebody comes and saves you. The most important office in this democracy is the citizen, the ordinary person who says, ‘No, that’s not right.’”

Biden, speaking in Chicago on Tuesday at the national conference of Advocates, Counselors and Representatives for the Disabled, denounced Elon Musk’s cuts to Social Security, his first public remarks since leaving office. “The last thing [beneficiaries] need from their government is deliberate cruelty,” Biden said, adding, “In fewer than 100 days, this administration has done so much damage and so much devastation.”

Clinton spoke at an emotional ceremony in Oklahoma City on Saturday morning to commemorate the bombing 30 years ago of the Alfred P. Murrah Federal Building, which killed 168 people. Clinton compared the way that city has come together with the current national divisions.

“It’s like everybody is arguing about whose resentments matter most, whose resentments are more valid, when it’s okay to stretch the truth a little bit to gain an advantage,” Clinton said. “If our lives are going to be dominated by the effort to dominate the people we disagree with, we are going to put the 250-year march to a more perfect union at risk.”

Clinton praised the service of federal workers at a time when Trump is slashing the federal workforce. He also made a case for humility. “It does you good every now and then to admit you’re wrong,” he said.

It is unusual for a single president to publicly excoriate his successor, historians say, given the American tradition of seamless transfers of power and the principle that the country has one president at a time. For three to do so in such short order may be unprecedented.

“What is really significant is this is happening before the end of the first 100 days of the Trump presidency,” Naftali said. “Ordinarily, former presidents give the current president space to establish himself and learn the rules of the road. … But these presidents already see the contours of the changes that President Trump wishes to bring.”

The White House did not immediately respond to a request for comment.

The three Democratic presidents spoke in terms of fundamental American traditions and values. But their relationship with Trump is also marked by personal animosity, as Trump has aimed attacks and insults at each of them or their family members.

He has repeatedly mocked “Sleepy Joe” Biden as a senile, elderly figure who has no idea what he is saying much of the time. Three months into his second term, Trump continues to regularly disparage Biden.

After Biden defeated him in 2020, Trump falsely claimed the election was stolen, an assertion he still clings to. He has attacked Biden’s son Hunter as a criminal and drug addict, recently ending Secret Service protection for Hunter and Biden’s daughter Ashley. (Hunter acknowledges spiraling into addiction after the death of his brother, Beau.)

When Obama first ran for president, Trump falsely suggested he had not been born in the United States, an assertion seen by many as racist. And he harshly attacked Clinton’s wife, Hillary, his opponent in the 2016 election, calling her “Crooked Hillary” as his crowds chanted, “Lock her up!”

The Democratic presidents, in turn, have said Trump’s violations of legal and democratic principles make him unfit for the presidency. Biden in 2022 called Trump supporters “a threat to our very democracy” and said the GOP under him had turned toward “semi-fascism.” He has said he ran for president in 2020 because of Trump’s support of white supremacists after violence in Charlottesville.

Obama, during the last presidential race, called Trump “a 78-year-old billionaire who has not stopped whining about his problems” and compared him to former Cuban president Fidel Castro “ranting and raving about crazy conspiracy theories.”

Clinton, who left office 24 years ago, mocked Trump’s age at the Democratic National Convention in August and again on Saturday, noting that he himself is younger. “Donald Trump — a paragon of consistency — is still dividing, blaming and belittling,” Clinton said.

This sort of rancor is not typical for the men who have held the country’s highest office. While presidents have been at odds before, there is often a sort of camaraderie in the small club of individuals who have borne the weight of the job.

After running a bitter race against each other in 1976, Jimmy Carter and Gerald Ford developed what Carter called “mutual respect” and “intense personal friendship,” agreeing that the longest to live would speak at the other’s funeral.

When Bush unveiled Clinton’s portrait in 2004, he spoke with affection, saying, “The years have done a lot to clarify the strengths of this man. … Bill Clinton loved the job of the presidency. He filled this house with energy and joy. He’s a man of enthusiasm and warmth.”

Such sentiments have not been much in evidence in recent years, even as the presidents appeared together at Carter’s funeral and Trump’s inauguration, both in January.

Obama, Biden and Clinton have all seemed struck by the sheer frenzy of the first stretch of Trump’s second term. At the end of his talk on Saturday, Clinton stressed that the United States has a wealth of institutions and assets.

He asked, “Are we really going to put them at risk to prove we’re always right and our resentments are more important than someone else’s?”