The defeat of Imperial Japan in WW II was earth shattering for the Japanese people. They had been told that their military and divine emperor were invincible and that they should be ready to sacrifice everything - includes their lives - for their country. When Emperor Hirohito announced Japan's surrender in the 'Jewel Voice Broadcast', his people were stunned (not least because they were hearing his voice for the first time). Though forced to disband their armed forced, Cold War tensions soon led to an American backed rearmanent and the creation of the Japan Self-Defense Forces, or JSDF in 1954.
If used in large groups; JSDF Soldier can be devastating and can destroy a base easily; if not in heavy fire.
Mortars are devastating against JSDF Soldier and can kill a group of them in a few hits if in the range of the impact. Spread your JSDF Soldier around so the mortar would have to hit each JSDF Soldier to kill it and that its impact would not affect other JSDF Soldier as well or deploy a few heavy cavalry to destroy it.
Use ranged infantry such as riflemen to support JSDF Soldier.
JSDF Soldier can be used as a distraction for many defenses and can help protect ranged infantry such as riflemen from heavy fire from defenses.'