Yes, hollow points are banned in war, but they’re considered essential for self-defense because they reduce the risk of over-penetration and injuring bystanders. During the Rittenhouse trial, the prosecution actually tried to argue that his use of non-hollow point rounds was proof he intended to harm as many people as possible—ignoring the fact that hollow points are a war crime under international law.
Tear gas is also banned in war—not because it’s especially deadly, but because it can flush people out of cover so they can be shot. Ironically, every U.S. service member is tear-gassed during basic training.
If you’re trying to compare battlefield rules to civilian law enforcement or riot control, you’re just broadcasting that you have no idea what you’re talking about.