Who are the first people you think of as activists? Malcolm X? Emmeline Pankhurst? Swampy? David Beckham?
Hang on. David Beckham. It doesn't feel quite right, does it? But Becks, green-and-gold scarf flung over the tattoo on his neck, has overnight become an activist whether he likes it or not.
Of all the movements -- civil rights, the right to vote, the environment -- the anti-Glazer-ownership-of-Manchester-United movement perhaps has the least civic relevance -- except, of course, for Man U fans or those concerned with the ownership of football clubs. But a movement it remains! And Becks is now its face, its sideburned poster boy.
In some ways it's like he's become a UN ambassador, Jolie-style, if you imagine that the Manchester United Supporters' Trust is a multilateral organisation responsible in some part for global security, development and well-being.
In other ways it's like he spotted a scarf and thought: "Photo opportunity!" on the back of a squashing defeat. Either way, Becks has clearly embraced the political significance thrust upon him:
I am a Manchester United fan and I support the club. I always will. I saw the scarf there and just put it round my neck. It's the old colours. That's all I know. It's nothing to do with me how it's run. That's to do with other people. I support the team.
Now that's the stirring language of a rabble-rouser, surely. This man knows how to stir a crowd, spearhead a charge, start a revolution. Watch out, world, Becks the activist is on the loose.