"It’s a terrible, terrible thing what’s going on with hate in our country, frankly, and all over the world. And something has to be done."

If only the person who said that had any self-knowledge or credibility. If he had the first, he’d start by apologizing for all he has done to fuel hatred in the past three years, and he’d cancel his remaining political rallies or tone them way, way down. If he had the second, we’d believe him. But he doesn’t. There’s no way to trust what President Donald Trump says, especially on civility and reconciliation.

After the horrific Tree of Life synagogue shooting in Pittsburgh by a gunman shouting, “All Jews must die,” after a white supremacist who couldn't break into a black church settled for killing two black people in a supermarket (and assured a frightened man in the parking lot that “whites don’t shoot whites”), after an unbalanced Trump fan mailed pipe bombs to some of the most prominent Democrats in America, what do we need?

Personally, I’d like as many former presidents as possible to appear together on a stage or set and tell us what we need to hear about America and its values: We are not a country of violent haters. We are believers in humanity, tolerance, freedom of speech and the press, and the gift of diversity.

Past presidents understood US history, values

Trump should turn over his rally venues to former Presidents Bill Clinton, George W. Bush, Barack Obama and, if they can make it, Jimmy Carter and George H.W. Bush. In their bones, after decades of steeping in American values and politics and world leadership, they’d all know what to say, even with no speechwriters laying it out for them. When the speechwriters did help these presidents, it did not strain credulity that they meant the words they said.

Jimmy Carter meant it when he said, after helicopters crashed in the desert on their way to rescue American hostages in Iran, "It was my decision to attempt the rescue operation. It was my decision to cancel it when problems developed in the placement of our rescue team for a future rescue operation. The responsibility is fully my own. ... I know that our entire nation feels the deep gratitude I feel for the brave men who were prepared to rescue their fellow Americans from captivity."

George H.W. Bush meant it when he said, after Iraq invaded Kuwait and he launched the Persian Gulf War known as Operation Desert Storm, “I ask for your support in a decision I've made to stand up for what's right and condemn what's wrong, all in the cause of peace. … America does not seek conflict, nor do we seek to chart the destiny of other nations. But America will stand by her friends.”

Bill Clinton meant it when he said, after the Oklahoma City bombing that killed 168, including 19 children, "We thank all those who have worked so heroically to save lives and to solve this crime. ... We pledge to do all we can to help you heal the injured, to rebuild this city, and to bring to justice those who did this evil."

George W. Bush meant it when he said, after the devastating 9/11 attacks, "These acts of mass murder were intended to frighten our nation into chaos and retreat. But they have failed. Our country is strong. A great people has been moved to defend a great nation. Terrorist attacks can shake the foundations of our biggest buildings, but they cannot touch the foundation of America."

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Barack Obama meant it when he said, after the shooting in Tucson, Arizona, that killed six and grievously injured then-Rep. Gabby Giffords, among others, "We may not be able to stop all evil in the world, but I know that how we treat one another, that’s entirely up to us. And I believe that for all our imperfections, we are full of decency and goodness, and that the forces that divide us are not as strong as those that unite us."

Obama meant it when he said, after the school shooting rampage in Newtown, Connecticut, "Can we honestly say that we’re doing enough to keep our children — all of them — safe from harm? ... I've been reflecting on this the last few days, and if we’re honest with ourselves, the answer is no. We’re not doing enough. And we will have to change."

And he meant it when he said, after a white supremacist gunman killed nine in a historic black church in Charleston, South Carolina, "As a nation, out of this terrible tragedy, God has visited grace upon us, for he has allowed us to see where we’ve been blind. He has given us the chance, where we’ve been lost, to find our best selves."

We believed these presidents, because they sounded like themselves, the people we had grown to know through years in public life. President Ronald Reagan was a politician, not a poet. But on the day seven astronauts died in the Challenger shuttle explosion, including elementary school teacher Christa McAuliffe, as America and its children watched, he wrote in his diary: “There is no way to describe our shock & horror.”

It was not a stretch when he told the nation, “Ladies and gentlemen, I’d planned to speak to you tonight to report on the State of the Union, but the events of earlier today have led me to change those plans. Today is a day for mourning and remembering.” Or when he said, quoting a poem speechwriter Peggy Noonan remembered from seventh grade, that the astronauts had "waved goodbye and 'slipped the surly bonds of Earth’ to ‘touch the face of God.' "

Trump is an aberration, not our new normal

Here is the dilemma: It doesn’t matter what Trump says now. No noble sentiment, no full-throated embrace of American values, will make us believe. There have been too many lies, too many divisions, too much trampling on and shredding of the most basic notions of who we think we are.

For the first time, I'm glad we have such a long windup to our presidential elections. In a matter of weeks, we'll see many Democrats start to emerge and, depending on the midterm results and special counsel Robert Mueller's report, maybe some Republicans as well. With enough will and hope, we should be able to focus on making a future that proves that these past few years are an aberration — a detour from the path we need and want to be on.

So yes, it would be nice if Trump summoned the words many of us would like to hear, the gestures we’d like to see. But they will be empty, and inevitably followed by jarring, inappropriate sentiments and events. Look at the rally in Illinois on Saturday, the same day as the Tree of Life shooting.

"It will require all of us working together to extract the hateful poison of anti-Semitism from the world," Trump said in acknowledging the massacre. But then he said that the New York stock exchange was open the day after the 9/11 attacks (in fact it didn't reopen until Sept. 17, 2001) and warned against bowing to “sick” people.

“We have our lives. We have our schedules. And nobody's going to change it. So we're here,” Trump told his audience. “And let's have a good time.”

Jill Lawrence is the commentary editor of USA TODAY and author of "The Art of the Political Deal: How Congress Beat the Odds and Broke Through Gridlock." Follow her on Twitter: @JillDLawrence