Because, as I understand it, that's what happened. The military elite didn't have any armor heavy enough to stop bullets that didn't also make them immobile and unable to fight at all.
That's also true of crossbows. It didn't have the extreme range of the English longbows but on a battlefield a quarrel could penetrate a knight's armor. That's why Pope Innocent III banned the weapon's use against Christians.
Because, as I understand it, that's what happened. The military elite didn't have any armor heavy enough to stop bullets that didn't also make them immobile and unable to fight at all.
That's also true of crossbows. It didn't have the extreme range of the English longbows but on a battlefield a quarrel could penetrate a knight's armor. That's why Pope Innocent III banned the weapon's use against Christians.