Going green, environmentally speaking, has been trendy for years. But over the past few weeks, for many people "going green" is a political act. Green, long a color representing Islam, has become the symbol of anti-government protesters in Iran, whose recent re-election of Mahmoud Ahmadinejad has drawn cries of fraud.

Many Twitter and Facebook users have colored their picture or avatar green in support of the protesters.

People love to participate and make their voices heard — as long as it's quick, cheap, and easy. That's why, for example, "Take Back The Night" and other anti-violence campaigns hold candlelight vigils and rallies. People can come together, hold candles for a few hours, talk about social problems, and then go home thinking that the streets are safer. While these sorts of events and efforts are said to "raise awareness," there is little evidence that they actually do any good.

The same thing is seen when people are asked to protest or boycott products. For example, for many years, there has been an Internet-based effort asking motorists to only buy gas on certain days---or, for example, not buy gas on May 15 to "protest" high gas prices; this would supposedly somehow bring the big oil companies to their knees.

The simple truth is that often there is simply nothing we can do as individuals. The problems and disasters are on a national scale, and require national (often multi-national) assistance. Ordinary citizens can pool their efforts to make a difference only indirectly, donating money or pressuring their elected officials to act.

It is of course natural to want to help and support people in distant lands, whether victims of hurricanes, genocide, or election fraud. When we can't find a way to help or affect change directly, we find ways to pretend to help. Pretending to help makes people feel better, providing the illusion that they are making a difference. (There are some direct measures which are actually helpful, such as Web-savvy supporters who have set up proxy servers to allow Iranian dissidents to get around state-sponsored censorship.)  

Real or alleged election fraud occurs regularly in countries throughout the world; Iran's may be the most recent example, but it is hardly the only one. Similarly, social repression and government censorship is nothing new; China, North Korean, and Cuba are a few examples. So why all this sudden, indignant moral outrage at the situation in Iran, a country whose politics few Americans have more than a superficial understanding of or interest in? Because it's the cause du jour, it's a cause that tens of thousands of Twitterers and Facebookers around the world can quickly and easily join — and just as easily forget about when the fad is over.

The desire to help is admirable, but just as all those yellow bumper sticker ribbons have done little to support our troops or end the Iraq war, displaying green on online profiles will do little to actually help. There is one place where showing green is a real act of defiance, change, and courage: in the streets of Tehran where people are being beaten and killed. Tinting your picture green from your laptop in the comfort of a Starbucks? Not so much.

Benjamin Radford is managing editor of the Skeptical Inquirer science magazine. He wrote about ineffective social protests in his book “Media Mythmakers.” His books, films, and other projects can be found on his website. His Bad Science column appears regularly on LiveScience.