First Lady Michelle Obama may have single-handedly saved the first day of the Democratic National Convention, with a speech that was ardent in its support for nominee Hillary Clinton, deft in its zingers at opponent Donald Trump — whom Obama never addressed by name — and warm in its appeal to the better nature of voters everywhere.

Of Monday night’s speeches, Obama’s came the closest to charting a path for Democrats, emphasizing the need for leadership that is stable, steady and mature, and that takes the awesome power of the presidency seriously.

“Because when you have the nuclear codes at your fingertips and the military in your command, you can’t make snap decisions,” she said. “You can’t have a thin skin or a tendency to lash out. I want a president with a record of public service, someone whose life’s work shows our children that we don’t chase fame and fortune for ourselves, we fight to give everyone a chance to succeed.”

By itself, that is a message that both parties should take to heart. Whether a candidate comes from the right or left side of the political spectrum, those elements should be immutable.

Meanwhile, Trump spent the evening tweeting nonsense about Elizabeth Warren’s cheekbones, again addressing her as “Pocahontas,” and intimating, without a shred of evidence, that he knew secrets about Sen. Cory Booker of New Jersey. It must pain intelligent Republicans to have to defend a nominee who treats his candidacy like a new toy bow and arrow, to be aimed at whomever displeases him.

Hillary Clinton has yet to close the deal with her own party, let alone the American public. Bernie Sanders did his part Monday night, with a powerful speech that gave a full-throated endorsement of his former rival — a distinct contrast with the tantrum thrown by Sen. Ted Cruz at last week’s convention, in which Cruz pointedly refused to support Trump after being given a prime speaking spot.

It is hoped that from this point on, with nominations locked in, Clinton and Trump will apply themselves to a serious discussion of the problems facing this nation, along with some details on how they would accomplish their goals. Both candidates owe voters that much.