This is what tokenism looks like

Hamnett has said: "A successful T-shirt has to make you think but, crucially, you have to act." Her point was that there had been not enough action; not enough change. Consequently, most of her 1980s T-shirt messages remain relevant today. "These problems - nuclear weapons, world poverty and famine - are still around," said Hamnett.

Yet we continue, ever hopeful, to wear sloganed T-shirts. Indeed, in a culture that is increasingly obsessed with "awareness", we also have ribbons, wristbands, badges and a world of virtual accessories: hashtags, Facebook likes, sharings, sloganed selfies. Online, we consume and wear each other's causes. We gobble them down and move on, as another flashes up on our Facebook page, or drifts into our Twitter feed.

I thought about this when I learned that David Cameron had refused to be photographed in Elle magazine's This Is What A Feminist Looks Like T-shirt, despite Ed Miliband and Nick Clegg agreeing to do so. Good on him, I thought. Perhaps he was demonstrating that he understands there is only so far gestural politics can go. If he had worn the feminist T-shirt, he might have been obliged to act like a feminist - to resist his desire to tell the ladies to "calm down dear" - and that, I suspect, would have been too much for him and a fair few of his supporters. For, I imagine, that one of the biggest virtues of wearing a political cause is that one can't actually help internalising it, and becoming it.

Users of social media face this kind of question from time to time, as another worthy cause pops up in one of our feeds. We are, in a virtual sense, being asked to wear the cause, to help increase awareness of it. And as we sit there, playing at armchair clicktivism, we can forget this is not quite enough.

The past few years have brought so many viral campaigns, from #StopKony to #NoMorePage3. All too often they have made us wonder at the current capacity for tsunami-waves of awareness, only to be disappointed by the seeming absence of action and change. #BringBackOurGirls was retweeted more than four million times and showed the world that huge numbers of us care about Nigeria's missing schoolgirls, and want to see international action, yet the girls have not been brought back; the trend has died. As the New Yorker's Naunihal Singh put it: "A viral hashtag, it seems, is a fever that breaks quickly."

At least we are becoming more aware. Or are we? Aren't we often presenting a cartoon version of the complex truth? The most successful viral video in history, #StopKony, made the atrocities in Uganda of Joseph Kony and the Lord's Resistance Army internationally infamous. But it was criticised for over-simplifying, fudging facts and failing to provide political or economic context.

A study of the Kony 2012 phenomenon by three experimental psychologists found that it was the over-simplification of the message - the identification of a "clear enemy", inducing "feelings of moral outrage" - that made it successful. They wrote that "complex problems - civil war, widespread injustice, and structural imbalance in central Africa, as well as between Africa and the rest of the world", had been portrayed "in simple terms as the product of one man's misdeeds".

In her book Ribbon Culture, Sarah Moore noted that often people were wearing ribbons less to make a statement about the individual issue than to show how sensitive they were. I worry that sometimes that's what's happening - we are wearing our causes online simply to show the world how caring we are. Of course, the virtue of what's happening online is that it is an ongoing conversation rather than being frozen in a single symbol.

But the real problem is that too many of us are just hoping someone else will do the actual work. Mostly when I click to share a viral campaign it's in the hope that if I spread the word a little, someone else might sort it out: perhaps a politician.

And this is partly why I'm uncomfortable with politicians indulging in hashtag activism. It's not David Cameron's job to wear a feminist T-shirt. As soon as a politician starts hashtagging or sloganing away, I can't help but think it's just a cover for the fact that they can't be bothered to do anything about the issue. They are just clicking away, like the rest of us, in the hope that someone else will sort it.

We should remember Hamnett's words as we click. It's not the wristbands, ribbons, T-shirts or hashtags that solve problems: we still have to act, and know the right course of action. But wearing the T-shirt can help us get there. When we put on and walk around in something, even virtually, it becomes part of us; it challenges us and infuses us. You're right, Dave. Don't wear the feminist T-shirt unless you're up for doing feminism. Walk the walk. Or, as you seem to have already decided, don't.