If you were in the Tokyo neighborhoods of Koenji on April 10, Shibuya on May 7, or Shinjuku on June 11, you might have seen (or more likely, heard) thousands of demonstrators weaving through the streets, waving signs and chanting slogans in opposition to Japan's atomic energy policies. In the past few months, some worried Japanese have turned to these marches to express their unease or outright anger over the handling of events at the Fukushima No. 1 nuclear plant after the March 11 earthquake and tsunami. For many, it has been their first time engaging in such a public and assertive display.

That includes Rumi Arai, who is better known as hip-hop M.C., Rumi, who made scalding appearances on the mobile stages leading the Koenji and Shibuya marches.

"The impression of protest in Japan is that it's for extremists on the right and left," she says. "I never expected to get involved in demonstrations or that sort of thing."