In his first on-camera interview in four years, Charles Koch told "Axios on HBO" that he "screwed up by being partisan," rather than approaching his network's big-spending political action in a more nonpartisan way.

Why it matters: Koch — chairman and CEO of Koch Industries, which Forbes yesterday designated as America's largest private company — has been the left's favorite face of big-spending political action.

Koch, 85, told me at his home in Wichita that he's disillusioned with his political results, but is optimistic about what he believes will be a less divisive strategy.

Koch said he wants to elect people "who are going to be champions for ... policies that empower people so they can realize their potential and succeed by helping others succeed."

The mea culpa began with the publication last week of a new book, "Believe in People: Bottom-Up Solutions for a Top-Down World," written by Koch with Brian Hooks, who has worked with Koch for 20 years, and is chairman and CEO of Stand Together, founded by Koch as a philanthropic umbrella.

"Boy, did we screw up. What a mess!" Koch writes. "[P]artisan politics prevented us from achieving the thing that motivated us to get involved in politics in the first place — helping people by removing barriers."

Koch admits: "I was slow to react to this fact, letting us head down the wrong road for the better part of a decade."

I asked Koch: In business, it would never have taken you so long to course-correct, so why the lag in the public square?

"I have made many mistakes in business," he said. "But business is a lot easier because the basic nature of it is not conflict. It's not divisive.

... Politics is win/lose."

Hooks told me the Koch network's new emphasis is on "social entrepreneurs":

"Teachers who are finding new and better ways to help turn their students on" ... people in "business who are empowering their employees to find their gifts ... "social entrepreneurs in communities."

And yet, the spending continues. Americans for Prosperity Action, the Koch network's super PAC, is pouring hundreds of thousands of dollars into Georgia, where twin Senate runoffs Jan. 5 will determine control of the U.S. Senate.

Hooks told me that's because the network has long been a supporter of one of the candidates, Sen. David Perdue (R-Ga.): "[W]e think that he can actually make a difference if he's returned to the Senate."

Koch said: "The problem with bad speech is not to shut it down, but to have more speech ... to have all different kinds so you have a chance to learn."

Koch said his "popularity contest is for one person: It's to be popular with me, because I've got to believe in myself." He said he makes no apology: "I'm not big into regrets."

"All the divisions today, we didn't create," he said. "They were there before, and they are there after."