A while back the Freedom Defense Initiative started taking out Islamophobic ads on buses around San Francisco (the original ads are not pictured; they are offensive enough I didn’t think it was worth it). Turns out, a vigilante (presumably, without super powers) has found a way to improve them — the ads are being defaced with new wording, and images of Kamala Khan, who is both the latest woman in the Marvel universe to take on the title of Ms. Marvel and Marvel’s first Muslim headlining character. Via Toybox at io9.
Feminist Philosophers 
If these were new ads I’d be unambiguously in favour. But as it is I’m left a bit uncomfortable: erasing someone else’s words (however hateful) doesn’t seem great on free-speech grounds. (Maybe the context makes it better? – i.e. the original ads have been out for a while so people have already read them. But then cities are inevitably transitory places – there are always new readers.)
David, why is it that if the ads were new you’d be unambiguously in favor?
Because then no existing speech would be being removed.
Oh! Did you mean that if the Ms. Marvel images were their own, and new, ads, rather than if the Islamophobic ads were new? I thought you meant that if the ads that were vandalized were new you would be in favor which is why I found your comment so befuddling (since the speech in the ads underneath wouldn’t have been able to be received if it were immediately covered up). As far as free-speech goes, I am certainly in favor of great limitations on the state’s ability to limit speech–but setting the state aside, I am concerned about how some speech effectively silences other kinds of speech. Note, though, that while vandalizing someone else’s words would be one kind of silencing, hate speech is plausibly another.
Ms Marvel is cool in so many ways: Marvel Comics only planned on doing seven issues. From what I understand, they didn’t have a definite deadline, but this was what they were estimating they would get before it got cancelled, and what they told the creators to expect work-wise. I suspect it the estimate had as much to do with it being a female-starring series as much as with it being a Muslim-starring series (my beloved She-Hulk got cancelled recently, for the fifth time!) But their projections turned out to be overly pessimistic – Ms. Marvel #11 comes out on the 4th, and she is still going strong.
I am not sure I agree with David about this violating free speech (but I am not sure I don’t agree). Am I violating someone’s free speech if I shout loud enough at a rally to drown out their conflicting shouts? The cases aren’t perfect parallels, of course (and this is, technically, vandalism, however awesome the vandalism might be). Worth thinking about.
At any rate, Kamala now has a new superpower: shuttin’ down the hate.
@Noetika: yes, sorry. Your second reading is right: “the ads” referred to the Ms Marvel ads.