This video is called Demonstration against Iraq war in Kumamoto, Japan.
Since the second world war, Japan (at the request then of the United States) has an anti-militarist clause in its Constitution.
The majority of people in Japan support keeping this clause.
This means it is illegal for Japan to have armed forces; let alone send them to other countries.
However, now, Koizumi, in the face of continuing mass opposition to the presence of Japanese soldiers in Iraq, has decided to bring them home.
As others, like in Italy, did before.
See also here.
Koizumi honoring World War II criminals: here.
- Iraq: US “Troop Surge” Magic Bullet Myth Lives On (lobelog.com)