(Note for Tumblr followers: This post was originally posted to my main, Blogger-powered blog, which is what I'm referring to as "my blog" and distinguishing from Tumblr throughout.)
So, I have been following, and occasionally tangling with, the nexus of bile, illiteracy, fanaticism, and towering ignorance that is the Moffat Hate community on Tumblr--a group Phil Sandifer recently, and quite accurately in my opinion, described as a "left-wing GamerGate"--for a few weeks now. (Not because I disagree that there are serious problematic elements to many of Moffat's works, but because they've been incredibly nasty to my friends without provocation, and also their arguments are terrible.) There is a LOT wrong with this community, which together with the Shakesville Kool-Aid assholes earlier this year has convinced me that organizing an online community on shared hate is a terrible idea, but I'd like to focus on one point: their complete inability to understand what Tumblr is and how it works.
One of the claims that seems endemic throughout the community is this idea that they can ask people to stop reblogging their posts, and that if people do not do so, it constitutes harassment. Not to put to fine a point to it, but this is utter nonsense, and it is nonsense specifically because of the way Tumblr is structured.
Tumblr, you see, is not like other blogs. Most blogs involve the creation of writer-curated spaces: for example, this blog is a space curated by me. I write posts, and while readers are free to comment, their comments appear within my space. I can delete comments, lock comments on a post, and so on. Other blogging platforms provide additional tools; if this were a WordPress site, for instance, I would be able to edit comments as well, and turn anonymous commenting on and off on an individual post level. On livejournal, I'd be able to create whitelists of users and set posts to only be visible to them.
What all of these have in common is that they serve to create a virtual space around my writing where I'm in control. Certainly people can interact with my writing from outside my space, for example by reading it through a feed or linking to it--but if they want to take part in the primary conversation about it, they have to enter my space.
Of course, the trade off is that that makes it possible, in theory, for a commenter to harass me. Because my blog is my space, it is possible for commenters to act in a way that invades my space, disrupting it in ways that make it no longer safe for me. It hasn't happened, but I've seen it happen to others twice, and heard about many other cases. (To be clear, I'm not saying that commenting on someone's blog is the only way to harass a blogger; I'm saying it's a way. There are others, and I'll address one later in this post.)
So what about Tumblr? The biggest difference between it and other blogging platforms is that Tumblr creates reader-curated, not writer-curated, spaces. The primary form of interaction with Tumblr is the dashboard, which is effectively a feed of blogs the user has chosen to follow, a stark contrast with Blogger, where my primary interaction is a back-end tool that displays my own posts and the comments of others on them.
The dashboard allows me to create a space in which I read the blogs I'm interested in, so it is straightforwardly a reader-curated space. However, that alone is not enough to argue that Tumblr is a reader-curated space; after all, I do have a discrete blog within Tumblr that contains only my posts and reblogs. Consider Facebook: it also defaults to a reader-curated feed, but is still ultimately a writer-curated platform (though not, strictly speaking, a blogging platform).
The key difference here is comments. On Tumblr, there is no way to enter another writer's space and comment on their post; you can, if they've enabled it, reply, but only they can see that. The only real way to comment on a post is to reblog it, which is to say rebroadcast it to your own followers--not the original writer--with your comments added.
There's an important word in that previous paragraph: "broadcast." That's key to understanding the difference between reader-moderated and writer-moderated spaces, because when you comment on this blog you are interacting with me, entering my space and saying words directly to me. That's not what a reblog is, however; it is a response to my words, yes, but not one that is said to me--it is instead said to your followers.
Which is not to say that it is impossible to harass someone on Tumblr. There are ways to interact with a writer--the aforementioned replies, though they have to enable those, asks and fan mail, which are effectively private messages (though asks can be published publicly at the recipient's choice). It is fairly straightforward to harass someone using these tools, and even possible using reblogs, since you receive a notification when someone reblogs your posts. You could, for example, go into someone's blog and methodically reblog their every post, spamming them with notifications.
This is, presumably, why Tumblr allows you to block a user, but it's quite telling what blocking does: the blocked user can no longer send you asks or fan mail and you no longer receive notifications regarding them reblogging you--but they can still follow and reblog you. In other words, it prevents them from interacting with you, but not from reading you and responding to their own followers about what they read. Which makes sense--you can stop someone from interacting with you maliciously in your space, which is you dashboard and activity feed, but you can't silence them. Just as on Blogger I can erase a malicious interaction in my space through comment moderation, but I can't (and shouldn't be able to) stop someone from saying whatever they want in their own space.
In other words, the Moffat Hate community isn't being harassed; they're being disagreed with, and trying to silence their critics. Reblogging their posts with added disagreement is not harassment any more than this post is harassment.