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"I wish I could turn back the clock and go back to 2010 and stop abuse on the platform by creating a very specific bar for how to behave on the platform," Costolo told a gathering of Los Angeles techies at the Upfront Summit, according to Axios.
Bullying on Twitter was a complex problem, and during his tenure as CEO, which ended in June 2015, Costolo said he became distracted by trying to accomplish other tasks.
He compared bullying to spam, explaining that the solution would need to involve making it more of an expense and waste of time to be the bully than the person receiving the abuse.
So, could policies put in place back then have perhaps changed the way Trump tweets? We'll never know.
Trump has a track record of retweeting racists Twitter accounts, and he's prone to name-calling. On Tuesday, he mocked New York Senator Charles Schumer for his tearful objection to Trump's immigration ban:
Nancy Pelosi and Fake Tears Chuck Schumer held a rally at the steps of The Supreme Court and mic did not work (a mess)-just like Dem party!
To be fair, while his tweets may rub some people the wrong way, Trump doesn't appear to have violated any of Twitter's rules.
However, the 45th President of the United States isn't above the rules on Twitter. He won't be granted any special protection if he violates Twitter's rules on violent threats, harassment, and hateful conduct.