Donald Trump is a race-baiting, woman-hating, one-man lie factory, but when he talks about campaign finance reform, I listen.

For me, the high point of last week’s Republican debate came when Trump was confronted with the fact that Democrat Hillary Clinton had been a guest at his most recent wedding.

True, she came, Trump said, but not because they like each other. She was there because he ordered her to be there.

“I said, ‘Be at my wedding,’ and she came to my wedding,” he said. “She had no choice because I gave to a foundation.”

Politicians, Trump says, will do almost anything for money, and since he has a lot of money, he would know.

“When they call, I give. And you know what? When I need something from them two years later, three years later, I call them. They are there for me.”

Clinton doesn’t deny going to the wedding, but she remembers it a little differently.

“I didn’t know him that well,” she told reporters after a town hall meeting in Exeter, New Hampshire. “I mean, I knew him, and I happen to be in Florida, and I thought it was going to be fun to go to this wedding because it’s always entertaining.”

“Thought it was going to be fun.”

Like Johnny Fontaine thought it might be fun to go to that wedding at the Godfather’s.

It’s hard for anyone to sound less sincere than Trump, but the former secretary gives it a good shot.

I’m willing to go out on a limb and predict that Donald Trump is not going to be the next president of the United States, but he has already done the nation a great service. He is letting us know what kind of government we have.

Because our next president, whether it’s Clinton or one of the 16 not-Trumps in the Republican field, will jump to attention when some billionaire snaps his fingers and says, “Be at my wedding.”

It’s not just Trump. Ted Cruz, Marco Rubio, Scott Walker, Jeb Bush and Carly Fiorina all went to a meeting this month of elite campaign donors put on by libertarian oilman Charles Koch, who, along with his brother, plans to spend $900 million on the 2016 race.

Bush, Walker, Chris Christie and John Kasich were among the candidates summoned to Las Vegas last year to be vetted by Sheldon Adelson, the 10th richest man in the world, who spent more than $100 million in the 2012 presidential election all by himself and may go even deeper this time.

This is how it works: Former Texas Gov. Rick Perry was soundly beaten in the 2012 Republican race, in part because the party base found him to be excessively thoughtful about immigration policy and partly because he was a terrible candidate.

He spent the last four years acquiring glasses, getting indicted for abusing executive power and memorizing a few jokes about his bad memory.

So far, he has failed to connect with voters. He’s out of money and mired with single-digit poll numbers, and he’s already had to stop paying his campaign staff.

That’s the kind of move that used to be the campaign equivalent of calling a priest for last rites. But Perry is not dead yet!

Thanks to two “outside” groups, both with the words “Opportunity and Freedom PAC” in their names, he still has hope. Perry has raised and spent about $1 million so far, but the super PACs have pulled together close to $18 million.

They can’t coordinate with Perry’s campaign, but they have their own people on the ground in Iowa and elsewhere who will be promoting his campaign and buying TV time.

While an individual can’t give more than $2,700 to a presidential campaign, there is no limit to how much a donor can contribute to a super PAC, which does essentially the same work.

Who needs voters if you’ve got donors like that?

There is a lot more at stake here than the outcome of this election. Our whole theory of government is at risk.

It’s bad enough that the system is rigged, but the fact that everybody knows that it’s rigged makes it impossible for regular people to trust anything their government does. The public’s cynicism and low expectations are as valuable to the big-money interests as the hyper-friendly officeholders.

A government run by and for a handful of wealthy families has a name – it’s called “oligarchy.” And America’s slide in that direction is a sad truth.

Even sadder, the guy who’s telling us the truth about it is Donald Trump.