Japan waged total war during WW II, period.
You are the only person on the planet arguing they didn't, and you are doing so by trying to change what "total war" means, to fit your personal definition, just so you can win an argument online.
Oh, I don't? If nerve gas is so awesome, why isn't it used more often? Why didn't they kick it into high production during WW II and use it at every front, every day, all the time? What about WW I? Why didn't all armies turn to chemical warfare only during WW I, if it is so great? Why even bother using bullets and bombs if it is the best weapon evar?
1. weather: nerve gas is susceptible to the weather, and can end up backfiring
2. gas masks
3. contamination: conquered areas become dead zones, which cannot be used for advancement
4. tactical storage: one lucky artillery shot to a nerve gas stockpile, and your whole camp can die
5. strategic storage and handling: moving around the stuff is dangerous
6. stockpile storage and discarding: over the course of years, the shells become dangerous.
In summary, nerve gas is best used against unsuspecting civilian populations you want to kill wholesale, in areas you intend to leave alone for a while. Unlike most weapons, when trying to deploy in a chaotic war theatre, gas agents and bio weapons have the extreme danger of backfiring.
BTW: I am getting some of this from
http://www.gulflink.osd.mil/library/randrep/mr1018.5.ch5.pdf
Note on page 4:
"During World War II, the Germans used aerial bombs and spray tanks for delivery. The vapor density allowed the agent to flow into lower terrain, trenches, bunkers etc., extending the hazard after the attack, which the Germans regarded as desirable."
So, at least according to this scholarly article, the germans did use nerve agents. I'll take his word over "I have read the sharia" Chiteng's word.
wrong again, Chiteng.
The first nerve agent of military significance was discovered by Dr. Gerhard
Schrader, a chemist conducting insecticide research with organophosphates in
1937.
http://www.gulflink.osd.mil/library/randrep/mr1018.5.ch5.pdf , pg. 2
LoL. Yeah, they really held back against the French and English.
Oh right, they didn't use the death star, so it wasn't total war.