We live in a hashtag world. What was once a sound bite is now a bit or a tag to make an issue go viral.

Last week I explained the value of the hashtag to my first-year students in global affairs and asked them to come up with their own viral marketing campaign. An 18-year-old college freshman said, "Hashtag, world peace for sale." Why for sale, I asked? That seems paradoxical. Indeed. She said that peace is not something you can buy like a product or service, but it's the most sales-worthy endeavor in the global marketplace of ideas.

Our hashtag class discussion came on the heels of the World Business Conference for World Peace convened by Hiroshima Gov. Hidehiko Yuzaki. We met in Hiroshima to discuss how to market the city and prefecture beyond the atomic bomb of August 1945 and U.S. President Barack Obama's speech last May.