[robowombat]

Mustard in its various forms is a highly persistent agent and for that reason was universally disliked by all militaries after WW 1. It was , however, the most effective agent for some 25 more years which is why the Italians used it in Ethiopia, the Spanish and French in the final campaigns of the Riff War and the Japanese apparently against China and the Soviets against Central Asian rebels in the 1920s.

[PAR35]

Then there were the hundreds (perhaps thousands - no one cared about the civilians) of casualties from US mustard gas in World War II.