According to President Trump, some Republicans in Congress and conservative media outlets, the Russia scandal is heating up.

No, not that one.

It's an alternative Russia scandal. And the claims go like this:

As secretary of state, Hillary Clinton approved the 2010 sale of a mining company to Russia. This gave the Russians control of 20 percent of U.S. uranium and placed U.S. national security at risk. In return, the Clinton Foundation received $145 million in pledges and donations.

Trump made this allegation during the 2016 campaign and again in an Oct. 19 tweet.

In the face of repeated fact checks, the president's claims have not withstood scrutiny. The president's critics call them part of an effort to divert attention from Justice Department special counsel Robert Mueller's investigation into possible collusion between the Trump campaign and Russia.

But because the story keeps surfacing and key Republicans are calling for hearings, here is a closer look.

Claim: Clinton played a key role in helping Russia gain control of U.S. uranium supplies.

The Russian state nuclear company, Rosatom, bought Canadian mining company Uranium One in 2010. Uranium One had, and still has, uranium mining rights in the United States.

For that reason, President Barack Obama's administration had to approve the deal. In a unanimous vote, nine U.S. government departments and agencies signed off. All are part of the Committee on Foreign Investment in the United States and included Clinton's State Department.

By all accounts, she was not actively involved. One of her deputies handled the matter, which was not considered controversial because uranium is widely bought and sold around the world for a range of purposes, from nuclear power plant fuel to medical treatments and research.

"It's a commercial market; it's a global market. Companies get bought and sold. Some of the companies that do the buying are controlled by foreign governments," said Matthew Bunn, who heads the Project on Managing the Atom, a nuclear policy research group at Harvard's John F. Kennedy School of Government. "That's the world we live in. It's a totally normal purchase."

Claim: Uranium One controls 20 percent of the U.S. uranium supply.

At the time of the 2010 sale, the U.S. Nuclear Regulatory Commission estimated that Uranium One held the rights to about 20 percent of U.S. uranium in the ground. But this figure is misleading.

The Washington Post reports that it is also outdated. It was based on uranium production capacity in 2010, which has since greatly expanded. Uranium One's share of mining rights is now far less than 20 percent of the U.S. total.

What is more, the U.S. is a tiny player in the world uranium market. The U.S. produced 1,126 tons of uranium last year out of global production of more than 62,000 tons, according to the World Nuclear Association. So U.S. production is less than 2 percent of the global total.

Uranium One produces a small and dwindling amount of that U.S. figure. Last year, it mined just 23 tons in the U.S. — about 2 percent of the small U.S. production.

Think of Uranium One's share as 2 percent of 2 percent. Or 0.04 percent of world production.

Some of Uranium One's U.S. uranium has gone to Canada and Europe, according to The Hill newspaper. But there is no evidence that any of it has gone to Russia.

Rosatom's more likely motivation for purchasing Uranium One was to gain access to the company's far larger uranium production in Canada and in Kazakhstan, which borders Russia.

Claim: U.S. national security has been put at risk.

Neither the U.S. nor Russia needs highly enriched uranium for nuclear weapons. The countries have more than 4,000 deployed or stockpiled weapons each, far more than the rest of the world combined. Both still have leftover stockpiles of highly enriched uranium that date to the Cold War.

"Both the United States and Russia, for some time, have had self-imposed moratoria on the production of weapons-grade nuclear material," said Kingston Reif, director of disarmament at the Arms Control Association in Washington, D.C. "Despite this, both the United States and Russia remain awash in highly-enriched uranium."

Under a program known as Megatons to Megawatts, Russia reduced its excess by dismantling nuclear weapons and sending the blended-down uranium to U.S. nuclear power plants.

"About 10 percent of U.S. electricity was coming from dismantled Russian nuclear warheads that used to be pointed at the United States," said Bunn, who worked on this issue at the White House during President Bill Clinton's administration.

That program expired in 2013, though Russia still sells uranium to U.S. nuclear plants.

Claim: The Clinton Foundation received $145 million in pledges and donations in exchange for the State Department's support of the Russian deal.

, who worked with Steve Bannon at Breitbart News, first made this claim in a 2015 book called Clinton Cash.

The New York Times said it used Schweizer's work to conduct its own investigation.

PolitiFact also looked into the matter and questioned the $145 million figure, noting that most of the donations and pledges came from Canadian businessman Frank Giustra, a friend of Bill Clinton. They were together in Kazakhstan in 2005, on a trip during which Giustra signed a major mining deal with that country, the Times reported.

Two years later, in 2007, Giustra merged his mining company with Uranium One and then sold his shares the same year. This was three years before the Russians bought the company, so it's not clear how Giustra would have benefited from the 2010 deal.

Giustra noted this in a 2015 statement in which he sharply criticized the Times for suggesting that his work with the Clintons was in pursuit of a business favor.

"I am extremely proud of the work that we have done" with the Clintons, he said. "I plan to continue that work long after the harsh glare of this week's media stories has faded."

Aside from Giustra, PolitiFact said its reporting could confirm about $4 million in donations to the Clinton Foundation from Uranium One investors in the years just before and after the 2010 Russian deal.

supports a wide variety of humanitarian projects around the world.

This episode raises the familiar scenario of overlap between the Clinton's private dealings and public actions and the potential for conflicts of interest. Yet a number of Clinton critics and news organizations have looked into the matter and have not presented evidence of wrongdoing.

As the Times concluded in its 2015 story:

"Whether the donations played any role in the approval of the uranium deal is unknown. But the episode underscores the special ethical challenges presented by the Clinton Foundation."

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