According to the setting of zombies in the film, it should take less than a week to eliminate these zombies. Koreans have died in 4 years.
If the soldiers in the film don't know the attributes of zombies at the beginning, and they don't know how to eliminate zombies, then they should know it if they live for a week or two.
Even if there are no missiles, there should be gasoline barrels, incendiary bombs, and explosives. Just find a football field or an open place, and as soon as the loudspeaker is turned on, the zombies will run in by themselves without burying them.
The director really has a misunderstanding of human intelligence.
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