Story highlights Donald Trump retweeted GIF edited to look like he had knocked down Hillary Clinton with golf shot

Kara Alaimo: By continually dredging up the past, Trump deepens the damage to his reputation

Kara Alaimo, an assistant professor of public relations at Hofstra University, is the author of "Pitch, Tweet, or Engage on the Street: How to Practice Global Public Relations and Strategic Communication." She was spokeswoman for international affairs in the Treasury Department during the Obama administration. Follow her on Twitter @karaalaimo. The opinions expressed in this commentary are solely those of the author.

(CNN) On Sunday morning, President Donald Trump retweeted a video that was edited to make it look like he was hitting a golf ball into the back of his 2016 election rival, Hillary Clinton, and knocking her down.

Kara S. Alaimo

It undoubtedly had the effect he wanted with some twisted sliver of his base: they paid attention and loved it. But it also had another effect he likely did not want: a much broader audience -- of his base, and beyond -- also paid attention and had a very different takeaway.

Let's begin with the nastiest, most offensive aspect of this -- the knocking-a-woman-to-the-ground aspect. Viewed through the lens of his previous actions and statements -- for example, his acknowledgment that "you know, I retweet, I retweet for a reason" -- his Sunday retweet reads like this: the President thinks violence against women is funny.

In fact, any man who thinks it's hilarious to intentionally aim to hit a woman belongs with a psychotherapist, at best, not in the White House. Violence against women, President Trump, is never funny.

And, whether or not this was Trump's intent, there's good reason not to promote even "joke" violence. Many studies have found that people who view violence in the media are significantly more likely to commit acts of physical aggression against others. In fact, many researchers say the risk of exposure to violence leading to actual violence is, as some have put it, as great as the risk of exposure to secondhand smoke from cigarettes leading to lung cancer.

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