"Was there a quid pro quo? Based on the Times reporting, there was certainly a lot of quid..."

"... (millions in donations that made it to a Clinton charity; a half-million-dollar speaker’s fee) and multiple quos (American diplomatic intervention with the Russians; approvals when the Russian firm offered a very “generous” price for Uranium One). The Clinton perspective is that, although the approvals were delivered by the State Department when Clinton led it, there is no evidence that she personally delivered them, or of the 'pro' in the equation. The Clinton campaign, in its response to the Times, noted that other agencies also had a voice in the approval process, and gave the Times a statement from someone on the approvals committee saying that Clinton hadn’t 'intervened.' The Clinton spokesman wouldn’t comment on whether Clinton was briefed about the matter. She was cc’d on a cable that mentioned the request for diplomatic help, but if there is a note in which she follows up with a directive—an e-mail, say—the Times doesn’t seem to have it. This speaks to some larger questions about political corruption. How do you prove it? Maybe the uranium people simply cared deeply about the undeniably good work the foundation is doing, and would have received the help and approvals anyway. In cases like this, though, how does the public maintain its trust?"

That's the first of "Five Questions About the Clintons and a Uranium Company," by Amy Davidson in The New Yorker. (And of course Davidson means everything that "an e-mail, say" seems to suggest.)