The battle over one of the last prominent bastions of unfettered free speech on the Internet has begun.

For months, Reddit's top leadership have toughened their rhetoric and policies to push back against harassment on the social news site. On Wednesday afternoon, the execs finally took action to make good on that by removing five offensive subreddits, or custom Reddit communities, for abusive behavior. The bans were the first for behavior reasons (as opposed to spam) under interim CEO Ellen Pao, but almost certainly not the last.

In the hours that followed, a small but vocal community of users revolted against the crackdown by creating new groups like PaoMustResign, now with more than 4,000 followers, and filled with defamatory posts comparing Pao to Hitler and Communist leader Chairman Mao. Her critics also launched a Change.org petition, with 6,500 supporters so far, pushing for her resignation.

Other commenters threatened to leave Reddit — or at the very least turn on ad blockers to ensure Reddit can't make money off of them. By Thursday morning, a thread called "[Serious] What are some good alternatives to reddit? serious replies only" had made its way to Reddit's influential front page, reminiscent of the days in 2010 when Digg users revolted by flooding its front page with links to Reddit.

"I'm sick of the politics and drama that is slowly creeping into every facet of the site," the user who created the thread wrote. Some who responded in the comments echoed that sentiment. "I believe that is the beginning of the end for the Reddit we all know and love," one wrote. "My suspicion is that the goal of E.P. and her gang is to begin monitizing [sic] the shit out of this site."

For Reddit, a limited amount of collateral damage here is acceptable. Reddit needs to snuff out the most hateful portions of its sprawling service in order to be a more hospitable environment for the new users (and, yes, advertisers) that it needs to become a truly mainstream business. If thousands, or even tens of thousands, of users disagree with the moves, so be it: Reddit has 172 million active users and it is going after many millions more.

"We did this incrementally so we could manage the response with our limited resources," a spokesperson for Reddit told Mashable, in response to questions about the backlash. "We knew there was a small but vocal minority of users [who would be unhappy]."

The brunt of the backlash was directed at Pao, Reddit interim CEO. Though hailed as a feminist icon outside Reddit for her involvement in a high-profile gender discrimination trial, Pao has a more mixed reputation among some of the Reddit faithful: She is viewed as an outsider pushing the site from its roots to make it more palatable to advertisers.

(Earlier this year, some users also accused Pao of deleting posts on Reddit criticizing her and her husband.)

In reality, the crackdown is part of a concerted effort from Pao and Alexis Ohanian, the Reddit cofounder who returned full-time as executive chairman after CEO Yishan Wong resigned abruptly in the wake of last year's nude celebrity photo hacking scandal. Ohanian has been more outspoken than Pao in pushing for measures that would turn Reddit into a "safe community" — and he continued to fiercely defend that thinking after the subreddit crackdown this week, as seen below in his exchange with a user.

Reddit's success or failure in trying to tame its worst offenders without destroying its vibrant communicate will likely reverberate throughout the technology industry. In recent months, Twitter has also taken steps to crack down on violent threats and harassment. Likewise, Imgur, the popular network for photos, began removing NSFW photos — only to ignite a backlash among its users.

In the shorter term, Reddit faces a more basic issue: It is effectively playing whack-a-mole. After Reddit removed the five subreddits, including one with a modest following called fatpeoplehate, users began creating clones.

As the top post on the newly created subreddit fatpeoplehate15 puts it: "I do not agree with what you say, but I will defend, with my life, your right to say it. That’s all."

The battle between free speech and hate speech rages on.

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