I would travel to Tokyo in 1993 and warn the leader of Aum Shinrikyo that his followers would bungle the job and that their sarin was not pure so they need to increase the concentration and use sharper umbrellas to ensure the plan is followed through correctly
Over nine million passengers ride the subway daily. A rush-hour attack could thus have caused chaos and massive numbers of casualties and fatalities. 32 However, the sarin used in the subway attack — like that used in the Matsumoto attack — was only 30% pure; sparing most of the subway ridership the disaster of a successful attack. The rudimentary method of delivery also prevented greater devastation.
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