Former Donald Trump ally and New Jersey Governor Chris Christie, now a 2024 presidential candidate, said Sunday that Trump acts like a "petulant child" when someone disagrees with him, and slammed the behavior as not befitting a president.

Christie related on CNN's "State of the Union" that Trump would lavish praise on people when he hired them and then rant about how incompetent they were when they left the administration.

"Here’s what he says about Rex Tillerson when he gets in. He says, he’s the embodiment of the American dream, former CEO of ExxonMobil. When he left, here’s what he said about him: he’s dumb as a rock and lazy as hell. About General Mattis, four-star general, 'mad dog Mattis,' he said he was our very best general and the closest thing that we had to Patton. When he left, he said he was the most overrated general in American history," Christie said.

Christie isn't telling the American people anything they don't know about Trump, but most other GOP hopefuls have not been as willing to point out Trump's flaws.

"Worst manager in the history of the American presidency"

"Look, either Donald Trump — if you believe what he said when they left, that means he doesn’t know how to pick the best people and doesn't know how to pick personnel. If you believe what he said about them in the beginning, the great stuff, then this guy is the worst manager in the history of the American presidency," Christie said.

"Either way, Republicans should listen to what he says; he’s a petulant child when someone disagrees with him. Whether it’s Bill Barr or John Kelly or General Mattis, Mick Mulvaney or General Milley, if you disagree with Donald Trump, the petulant child comes out, and he calls you names like the one you just mentioned and the ones I mentioned," he continued.

Christie is making the case for why Trump should not be president again, and why Trump may have said negative things about Christie himself, who was an adviser to Trump early on in his presidency.

There isn't much hope that Christie can be a serious contender for the GOP nomination. He's risen to third in New Hampshire's primary behind DeSantis (13%) and Trump (47%), but has a stiff hill to climb to get to a majority support.

Still, his anti-Trump message resonates with some voters and pokes at flaws many worry could hinder Trump's effectiveness in a second term.

Trump 32 points ahead

Most other polls have Trump above 50%, particularly after a second indictment many feel is as unfair as the first.

The Real Clear Politics average on June 18 had Trump 32.7 points above DeSantis, with a clear sympathy bounce from an indictment that could put him behind bars for the rest of his life if he is convicted of a crime that many other former presidents and officials have also committed.

Americans are revolting against a blatant double standard of justice that they consider unAmerican, and it seems that other GOP contenders may not have a real chance on the merits because of it.

He may be a "petulant child," as Christie described, but enough voters think he deserves a second chance at this point in the election cycle.

It is early days yet, but it really doesn't seem like Christie is the alternative voters will embrace over Trump.