This article is from the archive of our partner National Journal

"Follow the money." That apocryphal phrase, attributed to Watergate whistle-blower "Deep Throat," explains why the biggest threat to Hillary Rodham Clinton's presidential dreams is not her emails. It's her family foundation. That's where the money is: corporate money, foreign money, gobs of money sloshing around a vanity charity that could be renamed "Clinton Conflicts of Interest Foundation."

What about the emails? Hillary Clinton's secret communications cache is a bombshell deserving of full disclosure because of her assault on government transparency and electronic security. But its greatest relevancy is what the emails might reveal about any nexus between Clinton's work at State and donations to the Bill, Hillary & Chelsea Clinton Foundation from U.S. corporations and foreign nations.

Under fire, Bill Clinton said his namesake charity has "done a lot more good than harm"—hardly a ringing endorsement. One of his longest-serving advisers, a person who had worked directly for the foundation, told me the "longtime whispers of pay-to-play are going to become shouts."

This person, a Clinton loyalist and credible source, has no evidence of wrongdoing but said the media's suspicions are warranted. "The emails are a related but secondary scandal," the source said. "Follow the foundation money."

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Is the foundation clean? Is it corrupt? Or is the truth in the muddy middle, where we so often find the Clintons? Due to the fact that Hillary Clinton chose to skirt federal regulations and house her State Department emails on an off-the-books server, even the most loyal Democrat can't honestly answer those questions without an independent vetting of her electronic correspondence.

Without those emails, we may never be able to follow the money. Could that be why she hasn't coughed up the server?

Disclosure: I've known and respected the Clintons since the 1980s, when I covered state politics for the Arkansas Democrat (now the Arkansas Democrat-Gazette) and the Associated Press. Over the years, they've been kind to my family, and my career obviously benefited from their rise. Of all the public servants I've covered since moving to Washington in 1993, none approach the Clintons in terms of both strengths and weaknesses. While I've never called them corrupt (the Whitewater land deal was legitimate), I can tell you almost 30 years of stories about their entitlement, outsized victimization, and an aggravating belief in the ends justifying the means.

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Which is why I wasn't surprised when veteran Clinton chronicler Todd S. Purdum of Politco compared Hillary Clinton to Richard Nixon.

Not even Clinton's harshest critics could claim that Servergate (or Chappaquadata, or whatever it may come to be called) constitutes a high crime or misdemeanor. But it does connote a reflexive wariness about her enemies—a wariness that sometimes seems to border on paranoia—that has long dogged Clinton, and that struck at least a few old Nixon hands as familiar "...

"There is, of course," Purdum continued, "a bitter paradox in the fact that Clinton, as a young staffer on the House Judiciary Committee, actually worked on Nixon's impeachment."

I wonder what a young Hillary Clinton would think of a private charity run by a former U.S. president and a potential future president that collected hundreds of millions of dollars from countries and companies hoping to influence the pair. Actually, I don't wonder: She would think it smells.

And yet, a New York developer donated $100,000 to the foundation at about the same time Hillary Clinton helped secure millions of dollars in federal assistance for the businessman's mall project.

An aide close enough to Bill Clinton to be considered a surrogate son, Doug Band, set up Teneo, a company that New York Times columnist Maureen Dowd calls "a scammy blend of corporate consulting, public relations, and merchant banking." Band recruited clients from the foundation donor list while encouraging others to donate. "Its marketing materials highlighted Mr. Band's relationship with Mr. Clinton and the Clinton Global Initiative, where Mr. Band sat on the board of directors through 2011 and remains as an advisers," according to a 2013 New York Times exposé.

Money came in. Favors went out. While there is no direct evidence of quid pro quo, the foundation and its namesakes created this perception problem. They own it.

Bill Clinton noted Saturday that the foundation discloses most of its donations, a level of transparency beyond strict legal requirements. Nobody can argue that the foundation doesn't save lives and do other good deeds. "You've got to decide when you do this work, whether it will do more good than harm if someone helps you from another country," the former president said.

But there was a reason why the Obama White House asked the foundation to stop taking foreign donations while she served as secretary of State. It looks unethical. It may be corrupt. And yet, shortly after she left the State Department to begin presidential planning, the foundation opened up the foreign-money spigot.

It never stopped taking money from favored corporations, and recently it entered into partnerships with "at least six banks that were under investigation, involved in litigation, or had been fined by government agencies and regulators," according to a CNN investigation.

What did these companies and countries expect in return for their cash? Did the Clintons promise any favors? Those are fair questions—not partisan questions and not media "gotcha" questions. The Clintons are responsible for the management of their foundation. Hillary Clinton is responsible for stashing her emails in a secret server. She is running for president. The rest of us should follow the money.

This article is from the archive of our partner National Journal.