If the international spread of SlutWalk means anything, it means this: You should never underestimate the power of a simple idea. Nor should you expect that idea to remain simple for very long.

SlutWalk has become massive; its website lists completed or planned events in several dozen American and Canadian cities, with still more marches occurring in Australia, Sweden, the Netherlands, and the UK. But it’s worth noting that its inspiration was relatively small and local. This January, at Osgoode Hall Law School, a Toronto policeman giving a lecture on campus safety told students that, although he’d been “told not to say it,” he thought women should stop dressing like “sluts” so as to avoid being sexually assaulted.

Which, of course, is one of the oldest and worst lines in the book, when it comes to excusing rape. The fact is, anyone can be sexually assaulted; young or old, of any gender, of any race, conventionally attractive or not. The only common denominator in any rape or sexual assault is the presence of a sexual assailant. But the fact that a police officer, someone to whom a victim would be expected to turn to after an assault, could include victim-blaming in his “safety tips”: Well. It was a small incident. But it spoke volumes.

Hence, SlutWalk: Women and men taking to the streets to demand accountability from the Toronto police. Its goals were small and local focused; its message was equally simple and unequivocal. Its branding, however, stood out.

“Whether dished out as a serious indictment of one’s character or merely as a flippant insult, the intent behind the word [‘slut’] is always to wound,” said the organizers, “so we’re taking it back. ‘Slut’ is being re-appropriated.”

And so they did. The SlutWalk movement said — indeed, implicitly demanded — that those who participated in the march should be willing to identify as “sluts or allies.” It was an incredibly catchy, implicitly theatrical premise. Many of the protesters played that up, dressing in the sorts of revealing and provocative outfits that the Toronto policeman had condemned. The cameras tended to find those protesters first.

For some of those who joined, it was a simple way to identify. Some were sex workers, used to hearing that their impermissible sexuality was an excuse for police brutality, legal oppression, and violent assault or even murder. Others were women who enjoyed casual sex, or people who had sex in non-vanilla ways. For others, the label came less naturally; still, since any given woman can be labeled a “slut,” even the most monogamous or virginal among us, it made sense to march in solidarity. The simplicity of the message — no matter who you are, or how anyone else views your sexuality, you deserve safety — made it possible for the movement to gain ground anywhere that message rang true, until the outrage was not so much about anything that one man had done, but about the rage and pain that come with being sexual in a rape culture. And so, SlutWalk transcended Toronto, and the offending police officer, and became an international movement.

And yet. Several women of color have written that the event is based in white culture, white problems, and white assumptions — for example, the idea that one can expect “safety” when dealing with law enforcement in the first place.

“This event will not stop the criminalization of black women in New Orleans,” wrote Aura Blogando, “nor will it stop one woman from being potentially deported after she calls the police subsequent to being raped. SlutWalk completely ignores the way institutional violence is leveled against women of color. The event highlights its origins from a privileged position of relative power, replete with an entitlement of assumed safety that women of color would never even dream of.”

Still others have pointed out that the mere fact of wearing a “slutty” outfit does not always signify freedom, and feeling pressured to do so, or to reclaim the “slut” label, can in fact intensify and re-iterate their oppression: “In the post 9/11 climate,” wrote Harsha Walia, “the focus on a particular version of sex(y)-positive feminism runs the risk of further marginalizing Muslim women’s movements who are hugely impacted by the racist ‘reasonable accommodation’ debate and state policies against the niqab.” Simply telling women that they “can” or “should” be more sexually open or dress more scantily does not make sense, if those women are routinely persecuted for a seeming lack of sexual availability, or for wearing clothes that cover “too much” of their bodies. In a virgin-whore dichotomy, women are of course assaulted on both ends of the spectrum; anyone who plays the game will lose. That’s how rigged games work.

This matters. Because these are the dangers of making an international movement out of a simple, local protest. “SlutWalk” made sense, as an immediate reaction to the events in Toronto: When the police officer blames rape on revealing outfits, you wear a revealing outfit. When the police officer uses the term “slut” in a derogatory way, you use it in a positive one. But once it was exported, its flaws became apparent. It did not, and could not, speak to the needs of every woman; nor could it adequately sum up and address every facet of rape culture. And so, removed from its original context, it stopped being simple, and became simplistic.

Simple ideas are great for attracting crowds, especially when they come with camera-ready spectacle. But there is no way that SlutWalk can be made to bear the entire weight of anti-rape activism; relying solely on SlutWalk as our means of protesting anything — rape, sexism, even something as specific as slut-shaming — will invariably reveal that it does not measure up. No one protest or movement, not even one as widespread and as great at calling attention to itself as SlutWalk, can do that.

Feminism cannot live on SlutWalks alone. The fact that the movement has been so widely embraced does not mean that we should turn to it exclusively. What it means is that other protests can and should be happening; in addition to making the SlutWalk movement itself more inclusive and responsive, it’s essential that its organizers turn the mic over to other organizers, with ideas about protesting rape culture that extend beyond the “reclaiming slut” banner. The best thing for SlutWalkers now is to listen to the people who feel left out, and help them. The Sluts can and should keep Walking. But they should also recognize when to follow someone else’s lead.