If you need an index of just how influential the social aggregation site Reddit has become, consider the latest stir caused by the moderators of its most popular political forum, r/politics. When they took steps last week to ban submissions from a number of popular web domains, criticism quickly poured in from all directions. Few voices were as strident as Wonkette’s Rebecca Schoenkopf—”Little Hitlers,” she called them, with characteristic restraintbut virtually none were sympathetic.

Why would sites like Slate and Politico care what happens in the topical niches of Reddit? In no small part, it must be said, because Reddit drives traffic, and lots of it. For sites that specialize in political news and commentary, no section of the site is as pivotal as r/politics. Probably it doesn’t command quite the 3 million suggested by the subscription numbers in its sidebar, but the hundreds of thousands who do log in each month make up a significant source of potential ad revenue. That being a market few can afford to lose, the idea of a domain blacklist has made some online publishers understandably anxious.

So it was that Clara Jeffrey found herself on TLDR, On the Media’s digital culture blog, defending the journalistic bona fides of Mother Jones,the award-winning magazine she co-edits. “This is the internet’s premier user-driven discussion forum,” she told TLDR’s PJ Vogt:

We feel we add to the conversation. If Reddit users want to post our high quality, fact-led journalism, we think they should be able to do that. And if they have an issue with our journalism, they should be able to engage with it.

On Reddit itself, the bans created an uproar, with many r/politics users calling the blacklist “censorship.” More reservedly, media pundits have hinted that the controversy may come as a setback for Reddit’s reputation as a proponent of open discourse.

Earned mainly by its opposition to Congress’ failed SOPA bill and an early association with Internet advocate Aaron Swartz, that reputation can easily be overstated. The fact of the matter is that the process of growing from a scrappy start-up into the self-proclaimed “front page of the Internet” has been an uneasy process for Reddit. While its administrators may relish the idea of providing a haven for free speech, the way they’ve built their site doesn’t always lend it to that end.

Founded in 2005, Reddit grew up during the social network boom. For much of the next five years, its main competitor was Digg, but the expectations it faces in this decade were set by Facebook and Twitter. Those platforms connected accounts to one another via semantic relations, like friending and following. That, in turn, gave users a relatively high degree of control over the streams of information that flowed through their apps and onto their screens—so much control, in fact, that Facebook and Twitter are constantly innovating on their systems to introduce unsolicited relations, like those that connect users to advertisers.

To make the site more manageable, the administrators introduced a feature that would set a course down unexpected avenues.

By contrast, Reddit staked its fortunes on the rather old-fashioned Web page. The most visible instance is the site’s front page, where the highest ranked links of the recent past are displayed for your approval. Equally important, though, is the new page, where user-contributed links are queued in the order that they’re submitted. It’s largely there that the success or failure of new links is decided, both because older submissions are less visible to the causal browser, and because the site’s ranking algorithm gives extra weight to the first 10 votes.

By 2006, Reddit had already grown so active that users found it difficult to keep pace with its briskly moving new page. To make the site more manageable, the administrators introduced a feature that would set a course down unexpected avenues. Around certain topics, they created separate front and new pages, sometimes called subreddits, where users could post links without competing with other topics. As the site continued to grow, they added more, including an entire subreddit just for requesting new topics. Not without some trepidation, they added one for politics about 18 months later.

Initially, only administrators could create subreddits. By early 2008, the task of managing all those topical niches had grown burdensome enough that the admins decided to roll out a new feature: user-created subreddits. Users no longer needed to go through the request system to create their own topical forum. The process was scarcely harder than submitting a link, and anyone with an account was eligible.

As they proliferated,subreddits took shape as communal spaces, arranged around the shared resources of each subreddit’s local front and new pages. To manage all of those additions, the administrators delegated new powers to those motivated enough to create them. Any user that started a subreddit automatically became its moderator, with access to its controls, like the ability to remove submitted links or to promote other users to the status of co-moderator. Outside of their own subreddits—where, at least in principle, all users were made equal by the democratic power of the vote—moderators were the same as anyone else on the site.

Over time, the administrators have given moderators increasing latitude when it comes to defining those spaces, from altering the stylesheet that determines the look of the page, to implementing custom-built bots that automate moderator tasks. If you talk to the users crying “censorship” over the r/politics blacklist, many will tell you that the site’s recent problems are directly attributable to a cabal of users who have let those moderator powers go to their heads. The roots of the controversy go back farther than that, though.

They derive, first of all, from the site’s mixed orientation: primarily around subreddits, but with some features suggesting user-centricity. In the media atmosphere fostered by platforms like Facebook and Twitter, where everyone expects the ability to personalize what comes through their stream, the very notion of delegating moderation to someone else is bound to strike some as an offense. Further confusing the situation is Reddit’s subscription system. By default, logged-in users view the site from a home page that threads together links from the subreddits to which they’ve subscribed. That gives the impression of personalization, while simultaneously masking the distinct identities of the subreddits.

The two points of view are incompatible, bound to result in periodic clashes, and the evolution of the site encourages both.

The result of those mixed messages are easily read in the conflagration that occasionally engulf moderator decisions. Dissenters insist that moderators should limit themselves to removing spam and banning particularly aggressive trolls. Yet, the powers delegated to them, as well as the administrator’s reluctance to intervene in any but the most destructive controversies, are virtually an invitation to creative moderation. Reinforcing that impression are the new moderation features the administrators occasionally unveil, like manual approval for new submissions or the ability to mark link titles and user names with custom flair.

Those opposing perspectives on moderation are intractable precisely because they’re built into the way the site operates. Through their home pages, most users see the site as a stream of links and messages they ought to be able to control, while through the control panels of their subreddits, the corps of unpaid moderators see it is a collection of communal spaces to be shaped around specific topics or social goals. The two points of view are incompatible, bound to result in periodic clashes, and the evolution of the site encourages both.

The off-site outcry over the r/politics blacklist illustrates how Reddit’s popularity further complicates that dilemma. In the majority of subreddits, which are small enough to function as closed communities, flaring tempers over moderation are common enough to warrant an entire subreddit dedicated to drama. In the site’s largest subreddits, though, moderation changes have consequences not only for the local community, but also for the publishers and services to which they link. Those outside interests have more staked on the traffic Reddit sends their way than on the internal debate over how the site ought to work. Thus, when moderators announce rules that threaten to exclude major players, the drama can turn as viral as any meme.

On Monday, the moderators backtracked a bit, unbanning Mother Jones and promising policy reviews of the other blacklisted domains. Today, they followed up by unbanning The Huffington Post, which had recently reasserted its relevance by publishing an op-ed by President Obama. For now, however, they’re standing by the decision to maintain some form of blacklist. That partial reversal may not be entirely attributable to hostile opposition from their fellow contributors; chances are the moderators are just as intimidated by the scrutiny they’ve received from media outlets like Slate and On the Media.

Therein lies the strangest hazard of moderating a subreddit. Given its inherent tension between personalization and moderation, the size and influence of the site all but ensure that moderators will sometimes find themselves dealing with controversy on a stage far above their paygrade. For most moderators, that’s no paygrade at all, since only the administrators are actually employed by Reddit.

In nearly any other media outlet this size, policy and design decisions would fall almost entirely on people who are responsible to the company, but the majority of Reddit’s moderators can count on precious little in the way of guidance or support. The company has given them every inducement to experiment with the way subreddits work, and when they do, they’re likely to be vilified by their fellow users and, increasingly, the press. Preventing that would require a major realignment of how Reddit works.

Nor is r/politics unique in that regard. Earlier this year, another of the site’s most popular subreddits, r/atheism, underwent similar upheaval. What made both subreddits especially prone to meltdown was their inclusion in the default list of subreddits to which new users are automatically assigned. As a result, they grew fast, developed contentious communities, and reacted sharply to the imposition of new rules.

The administrators have since revoked the default status of both, but the antipathies that ignited those conflicts were never entirely unique to r/politics or r/atheism. To the extent that they’re built into the basic features of the site, it’s a good bet we haven’t seen the last mutiny.