Julian Zelizer is a history and public affairs professor at Princeton University, editor of "The Presidency of Barack Obama: A First Historical Assessment" and co-host of the "Politics & Polls" podcast. Follow him on Twitter: @julianzelizer. The opinions expressed in this commentary are those of the author. View more opinion articles on CNN.

(CNN) Reading anything into a short, grainy tape recording is difficult. But from the moment that CNN's Chris Cuomo shared one of the Michael Cohen tapes, experts have sliced and diced the audio to figure out exactly what then-candidate Donald Trump knew about a payment to keep his alleged affair with former Playboy playmate Karen McDougal off the front pages.

One of the most remarkable aspects of the tape is just how normal Trump sounds when the cameras are not on. He carries on his conversation with one unnamed person (likely on the phone), as well as with his lawyer Michael Cohen, in a relatively controlled and deliberative voice. This is not the same Trump who we heard and still hear speaking in half-sentences. Nor is it the Trump who continually tosses out statements made on Fox News to his audiences, simply to stir up the base.

No, on this tape we hear a little bit of a methodical and controlled candidate who is trying to figure out how to handle a potential problem in his campaign -- how to kill an embarrassing story. He listens, absorbs and responds. He knows what is going on, and he wants a workable plan.

While we certainly can't read too much into this short piece of audio, it does create the possibility that Trump is much more strategic about how he conducts his business. Though many critics depict him as a deranged and unstable leader, while supporters love to think of him as "just being himself," the tape suggests another possibility.

Namely, Trump is playing a part in front of the cameras -- the norm-breaking, in-your face conservative populist who is attempting to maintain his razor-thin electoral coalition of loyal Trump fanatics, stalwart Republican voters and disaffected Democrats. When he conducts a press conference in Helsinki with Russian President Vladimir Putin in which he defends the Russians and attacks the American intelligence community, there is a thought-through rationale for why he does so. When he tweets out provocative statements about NFL players or political opponents, he is attempting to trigger certain responses and to push the conversation in specific directions. When he allows children to be separated from their families at the border, he is trying to send a harsh message.

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