Steven Spielberg has withdrawn from his role as artistic adviser to the Beijing Olympics to protest China’s policy towards Darfur. Seemingly, yet another example of “celebrity activism” around human security issues.

I blogged about this before. As I continue to think about the role of celebrity activism in human security campaigns, I’ve been pondering who actually counts as a celebrity? Performers clearly do. But what about other well-known members of the entertainment industry – writers, producers? What about well-known figures who perform public, rather than media roles? In a digital world, where do the lines blur between political, cultural and religious “celebrities”? Also, is there an analytical difference between celebrity “activism” and “celebrity activism”?

An example of the former conundrum. The transnational advocacy literature sometimes refers to Princess Diana’s role in championing the landmines issue. But was her role more analogous to that of Bono re. debt relief? Or more analogous to Hilary Clinton’s championing of attention to sex trafficking? Was Diana a celebrity in the movie-star sense or a political figure in the statesperson sense? What about Al Gore? Is he a former president or a movie star? Few would doubt that his “celebrity” activism has drawn new attention to climate change as an issue. And are religious figures such as the Dalai Lama or Pope genuine “celebrities”? Are you a “celebrity” if you are not routinely featured in the tabloids?

And what do we mean by activism anyway when it comes to celebrities? There is personal activism, where a celebrity uses his or her renown as soft power in their own civic work – as the LiveAid events depicted in the Nickelback video suggest. And then there is the embedding of activism into media outputs produced by celebrities themselves – such as the video “If Everyone Cared” itself or the film “Blood Diamond.” Are these activities really comparable? Should they not be disaggregated somehow in order to gauge the relative influence of celebrities in global politics?

Some careful attention to the actual role of celebrities in transnational campaigns – for better or worse – is long overdue by IR scholars. But there are conceptual problems to deal with first. Who can offer a parsimonious definition of “celebrity” or of “celebrity activism” that might guide rigorous research on the subject?