英语访谈节目:亿万富翁大卫·科赫去世

And David Koch has died. He was a billionaire businessman, one-time vice presidential nominee, and conservative mega-donor. John Yang looks at his life and legacy.

JOHN YANG: David Koch helped his brother Charles expand the Wichita-based Koch Industries into one of the largest privately-held corporations in the world. He quickly became a notable figure in elite New York social circles. The business eventually became the fuel behind one of the highest-spending political action groups in modern American politics, Americans for Prosperity.

NARRATOR: Americans for Prosperity is responsible for the content of this advertising.

JOHN YANG: The anti-tax, pro-small government group poured hundreds of millions of dollars into conservative candidates and causes, often through untraceable so-called dark money contributions.

MAN: The president's doing a mediocre job.

JOHN YANG: The oil-and gas-based Koch network spent just under $400 million on the 2012 election, an unparalleled sum at the time that filled the airwaves with attack ads.

NARRATOR: President Obama's health care law is actually one of the largest tax increases in history.

JOHN YANG: Targeting President Obama and the Affordable Care Act, while long denying climate change.

DAVID KOCH, Co-Founder, Americans for Prosperity: I'm basically a libertarian.

JOHN YANG: In a 2014 interview with ABC's Barbara Walters, Koch defended his political contributions.

BARBARA WALTERS, ABC News: Do you think it's fair that just because you have billions of dollars, you can influence elections?

DAVID KOCH: Well, I contribute to public candidate campaigns, and there's a federal limit on how much you can contribute to each individual candidate. I obey the law in that regard, and feel I'm doing it properly.

JOHN YANG: Limits on corporate donations to political candidates had been lifted four years earlier, the result of the Citizens United Supreme Court battle that the brothers had helped fund. The Koch brothers famously didn't endorse Donald Trump in 2016, over concerns about free trade. But their group did target several Democratic senators in the 2018 midterm elections. In addition to politics, Koch gave millions to cancer research, some PBS programs, and a full wing of the Smithsonian's Natural History Museum. For the PBS NewsHour, I'm John Yang.