More interesting is how the emails leaked out. When the leak occurred, the DNC and government officials said that Russian hackers were to blame. On Sunday, Clinton campaign manager Robby Mook went on ABC’s This Week and repeated the allegation.

“What's disturbing about this entire situation is that experts are telling us that Russian state actors broke into the DNC, took all these emails and now are leaking them out through these Web sites …. for the purpose of helping Donald Trump,” he said. Mook also questioned whether the emails had been “doctored.”

There’s a whiff of CYA to this line of argument, the type of pleading delivered by a DNC that’s been caught in a bad place. Mook’s question aside, there seem to be no serious cases where DNC employees have claimed their emails were altered. But just because Democrats seem to be looking for an excuse doesn’t mean their excuse isn’t valid.

The FBI said Monday morning that it is investigating the email leak, and there’s a stack of evidence connecting the leak to Russia, which DefenseOne’s Patrick Tucker helpfully rounds up. Thomas Rid has more at Motherboard. The New York Times suggests the question is not who did it, but on what authority: “Whether the thefts were ordered by Mr. Putin, or just carried out by apparatchiks who thought they might please him, is anyone’s guess.”

That all suggests a disturbing chain of events: Russian-government hackers worked their way into the Democratic Party’s email system, smuggled out what they wanted, and then delivered the cache to WikiLeaks right on the eve of the Democratic National Convention, and right after Donald Trump’s coronation at the Republican National Convention, to maximize the negative impact of the revelations. (A WikiLeaks tweet in which the organization gives itself a pat on the back can be read as an ironic commentary on a Putinist plot.) The Russian government, in other words, could be attempting to meddle with the results of the U.S. presidential election. As journalists who have covered Russia, as well as the top Democrat on the House Intelligence Committee, pointed out, such an action would be in line with previous Russian interference in foreign elections, most of them closer to home.

The Clinton campaign has already begun making a case that Donald Trump is not just sympathetic to, but actively in league with, Vladimir Putin. One candidate lodging such an allegation against another would be effectively unprecedented, the Times notes. (Foreign interference, however, might not be; nor, needless to say, is the U.S. innocent of meddling in foreign elections.) Michael Isikoff reports on how a consultant working for the DNC started getting frequent messages saying her account was being targeted by “state-sponsored actors” after she began investigating Trump campaign manager Paul Manafort, who previously worked for a Putin client. “Since I started digging into Manafort, these messages have been a daily oc­­­­currence on my Yahoo account despite changing my password often,” she wrote to a DNC employee.