Russia. China. A 400-pound man sitting in bed. All suspects in the hack of the Democratic National Committee this summer, Donald Trump said during Monday evening's presidential debate.

Who did it? We may never know, according to Trump.

It's part of a one-two combination to turn the hacking attacks back against the Clinton campaign, and very similar to an argument made by Russian President Vladimir Putin in a Sept. 5 interview with Bloomberg.

First, question the source of the hack, and in general the ability of investigators to assign blame for electronic attacks. Intelligence officials and electronic security firms have said the evidence points to Russia, but how do we really know that?

Second, return attention to the information in the leak, a damaging exchange between Democratic National Committee officials that prompted the resignation of former DNC chairwoman Debbie Wasserman Schultz.

"I don't think anybody knows it was Russia that broke into the DNC," Trump said during Monday's discussion of cybersecurity, according to a transcript of the debate. "[Clinton]'s saying Russia, Russia, Russia, but I don't — maybe it was. I mean, it could be Russia, but it could also be China. It could also be lots of other people. It also could be somebody sitting on their bed that weighs 400 pounds, okay?"

There is a point there. Tracing hacking attacks is hard, relying on clues inside of code about keyboard language and the hacking team's working hours, lists of previous targets, methodology and other evidence, some of it circumstantial. Andrei Soldatov, one of Russia's leading experts on surveillance and the security services, said in an interview earlier this month he was skeptical about accusations by U.S. officials that named specific Russian security agencies behind the attack.

"I'm pretty sure it was a state-backed effort, but it could mean many things, including a cooperation of private actors with the state agencies with encouragement from the Kremlin," he wrote in a message.

That said, it's hard not to notice that Trump and Putin have the same strategy to deflect questions about the attack. First, say that hackers can't be traced.

"I know nothing," Putin said in the interview. "There are a lot of hackers today, you know, and they perform their work in such a filigreed and delicate manner and they can show their 'tracks' anywhere and anytime. It may not even be a track; they can cover their activity so that it looks like hackers operating from other territories, from other countries."

Now that we don't know who did it, return attention to the content.

"Besides, does it really matter who hacked Mrs. Clinton’s election campaign team database?" Putin said. "Does it? What really matters is the content shown to the community. This is what the discussion should be held about. There is no need to distract the attention of the community from the essence of the subject substituting it with secondary questions dealing with the search of those who did it."

The one-two combination. Here's what Trump said:

"You don't know who broke in to DNC. But what did we learn with DNC? We learned that Bernie Sanders was taken advantage of by your people, by Debbie Wasserman Schultz. Look what happened to her. But Bernie Sanders was taken advantage of. That's what we learned."

An earlier version of this article incorrectly stated that Russian security analyst Andrei Soldatov believed that the DNC hack was not a state-backed effort.

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