Sinéad O'Connor's open letter to Miley Cyrus isn't entirely helpful to women. While O'Connor's warnings about young artists being exploited by the music industry should be taken seriously, the implication is that naked or other sexual images of women inevitably entails the woman being a victim. Why should this be the case? How boring a world without any images of nudity would be. There would be no celebration of the immense power of sexuality, no eroticism.

O'Connor doesn't use the word objectification in her letter, but the idea that looking upon women's naked or semi-naked bodies necessarily means the disempowerment of women underlies her words. When O'Connor writes, "you ought be protected as a precious young lady", and says that female nudity makes young women "prey for animals and less than animals", she equates women's bodies with vulnerability and violence.

It's a similar rhetoric to that of the No More Page Three campaign. A quote on its website, for example, states that the Page 3 image is "a sex object" and then immediately, with no other nuance, relates this to "300,000 women being sexually assaulted and 60,000 raped each year".

Perhaps you can already see the problem here. It is not women's bodies or images of them that cause the exploitation of women or violence against women. The perpetrators are to blame. If women's bodies were to blame for any violence or exploitation of women, then rapists would be justified in claiming their victims were asking for it by looking attractive. The rhetoric of objectification actually feeds that which it claims to protect women against – the equation of female nudity with exploitation and violence. What the world needs is not the idea that women are precious victims. Women need to be able to behave in a sexual way without exploitation or violence being considered a necessary outcome.

O'Connor's line "your body is for you and your boyfriend" is not far off from saying that a woman should only be seen by her husband – which may be OK if that is what she wants, but where does that leave women who don't have boyfriends or husbands, or who want to be promiscuous?

We live in times when hugely powerful women like Rihanna and Beyonce could be said to objectify themselves and other women in their videos. But the simplistic formula that images of women's bodies are always objectifying is old-fashioned and plays into the idea of feminists as asexual. Young women need to know that when they take off their clothes, they are still in charge of themselves.