Dubuque, Iowa CNN —  

Donald Trump uses Twitter to speak, to poke and to retweet.

And his penchant for public musing has turned into a key element of his campaign – allowing him to steer public debate and train attention on whatever issue, or chosen enemy, he desires.

So what’s in a retweet?

That’s one of the questions he was asked in an explosive news conference centered mostly on immigration in Iowa Tuesday. But Trump also shared his Twitter philosophy in response to reporters’ questions.

Reporter: Can you tell us your retweet strategy? Do you endorse what you retweet?

Trump: Well I do retweets, and I mean, to a certain extent, I do, yeah. I think that’s right. Do you want me to say no? You know, I retweet, I retweet for a reason.

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Later, he was asked about specific targets of his tweets: Fox News host Megyn Kelly and competing presidential candidate Lindsey Graham.

Reporter: What is the strategy behind the Twitter fights? The late night tweeting about Megyn Kelly or Lindsey Graham.

Trump: It’s two seconds, you do a couple of tweets.

Reporter: Why?

Trump: Because when people treat me unfairly, I don’t let them forget, and maybe we should have more of that in this country, and maybe the country wouldn’t be pushed around so much.

And his tweets came up a third time later in the session, though Trump may have misheard “tweets” for “speech” at first.

Reporter: One more thing about your tweets: Do you write them yourself?

Trump: I think about them myself.

Reporter: Did you write the tweets?

Trump: Very interesting, because a lot of people have been asking me. In Alabama, I got very high marks for the speech and I honestly feel and it’s one of the things I look about – I’m always on live television. And if you’re on live television every 3 or 4 days, you’ve gotta say things differently. Can’t be on the same – get the same speeches, right? I think about my speeches, and I don’t believe in teleprompters, although it’s very easy, would I like to go and stand up and read a speech for an hour and just read … In fact, I jokingly say, if you’re running for president, you shouldn’t be allowed to use teleprompters. So I think about my speeches a lot, I think about what I’m going to say, but I essentially don’t use notes and I definitely don’t read the speeches.

Reporter: Late at nights when you’re on Twitter, writing tweets, do you write them yourself?

Trump: I do a lot of things by myself, people would be surprised.

Reporter: Do you write all your tweets?

Trump: People are shocked at how smart I am.

Reporter: Do you type your own tweets?

Trump: Thank you.