Global or local? It's a question that crops up without fail when I talk to students of international advertising. The answer, I think, is both. You're looking for a poignant idea with potential for local adaptation. Because the world is far from globalized. It's both flat and bumpy.
Fashion is a perfect example of this. When we were in Pamplona the other week, my wife remarked that the people there dress in a very specific way. I can only describe it as Ralph Lauren with a Spanish twist. You see this all the time when you travel. We may all dress in Zara, H&M and Uniqlo, but the way we wear the clothes varies from culture to culture. An Italian guy is not going to wear a black sweater the same way I do (his is probably slung over his shoulders).
As the world becomes more connected, I believe we will cling more passionately to our local identities. It's not just a question of national boundaries – I also believe in the hyper-local. I recently changed my address temporarily from the 9th arrondissement of Paris to the 18th, near metro Jules Joffrin. The atmosphere there is totally different; so are the dress styles of the local population. Next year I'll be moving again, to Clichy. Fifteen minutes from the Champs-Élysées, but a world away. Opponents of globalisation worry that we will all end up looking alike. But it's extremely unlikely.