Ten tanks rushed to the spot and formed a diagonal column. All at once,
they started firing large, rapid-fire cannons—the pride of the military—
from the tops of the tanks.
But what should happen? Just moments before, Godzilla had smashed
through barbed wire charged with fifty thousand volts of electrical current,
but that didn’t even faze him. Not surprisingly, the cannon fire didn’t affect
him either.
The Japan Ground Self-Defense Force had poured all their hopes into
their preparations, but even this last line of defense was completely crushed
underfoot by the monster.

Godzilla: Godzilla in Tokyo
Godzilla Attacks the Metropolitan Center