The power and greed of billionaires in the United States is threatening the country.

So says Bernie Sanders, the 77-year-old senator from Vermont who tried unsuccessfully to win the Democratic presidential nomination in 2016.

"We live in a nation owned and controlled by a small number of multi-billionaires whose greed, incredible greed, insatiable greed, is having an unbelievably negative impact on the fabric of our entire country," Sanders told Paul Jay, CEO and senior editor of The Real News Network, in an interview posted Thursday.

Sanders, who has become a political figurehead for the liberal end of the Democratic Party, said billionaires and their greed are to blame for any number of social problems in the United States.

"When we deal with climate change, when we deal with the economy, when we deal with housing, when we deal with criminal justice or immigration issues, we have got to deal with those in a holistic way, and understand why all of that is happening. Not see them as silo-ized separate issues," Sanders said. "A lot of that has to do" with the pervasive power of the ultra rich in this country, he said.

It is the responsibility of America to look at the extreme gap between the rich and the poor, Sanders said.

"It is not just that the one tenth of 1% owns more wealth than the bottom 90%. They don't put their wealth underneath their mattresses, right. They use that wealth to perpetrate, perpetuate their power. And they do that politically" - @BernieSanders

"What you have here is, first of all, massive income and wealth inequality. And as a nation we have got to think from a moral perspective and an economic perspective whether we think it is appropriate that three people, one, two, three, own more wealth than the bottom half of the American society," Sanders said. (A November 2017 report published by the progressive think tank Institute for Policy Studies found that Bill Gates, Jeff Bezos and Warren Buffett collectively had more wealth than the 160 million poorest Americans, or half the population of the United States.)

"You know, that's really quite outrageous, and it's appropriate that we take a hard look at that," Sanders said.

The disparity Sanders refers to is getting worse. A report released in July from the nonprofit, nonpartisan think tank Economic Policy Institute shows that income inequality has increased in every US state since the 1970s. A family in the top 1 percent of families in the United States in 2015 (the most current data available) was bringing in 26.3 times as much income as a family in the bottom 99 percent, according to the report.

"While the degree of income inequality differs across the country, the underlying forces are clear. It's the result of intentional policy decisions to shift bargaining power away from working people and towards the top 1 percent," said Mark Price, an economist at the Keystone Research Center in Harrisburg, Penn., in a written statement released with the report. "To reverse this, we should enact policies that boost workers' ability to bargain for higher wages, rein in the salaries of CEOs and the financial sector, and implement a progressive tax system."

The influence wielded by the ultra-wealthy is visible in politics and the media, according to Sanders.

"They don't put their wealth under neath their mattresses, right. They use that wealth to perpetrate, perpetuate their power. And they do that politically," Sanders said. "So you have the Koch brothers and a handful of billionaires who pour hundreds of millions of dollars into elections, because their Supreme Court gutted the campaign finance laws that were in existence, and now allow billionaires quite openly to buy elections."

Charles and David Koch are each worth more than $48 billion, according to Forbes. Their wealth comes from their family business, Koch Industries, the second largest private company in the United States, according to Forbes. Though their PAC does reportedly spend hundreds of millions on elections, that includes funds raised by a network of about 300 donors, according to The Washington Post.