system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5 Why is using chemical warfare so much worse than dropping bombs?
gpt
DOD chem/bio defense testing project manager reporting in.

Think of a bullet. You shoot it, and it flies until it either falls to the ground or hits something. In one second, its lethality is nonexistent.

A conventional bomb or mortar or grenade is a similar story - it goes boom once at impact and it no longer represents a threat. However, every so often, they don't explode, leaving UXO, UneXploded Ordnance. This is dangerous and people die from them if they go boom later.

A land mine is dangerous to non-combatants. After the war is over and a peace treaty is signed, some kid could walk into a forgotten mine field and be killed.

Chemical weapons have varying persistence - some hang around longer.

The G-series agents (tabun, sarin, soman, cyclosarin) vaporize and blow away rather quickly. Sure, there is still some left sticking to stuff, but for the most part, the hazard is gone.

We use thickeners in it so that it will stick to stuff when a chemical bomb explodes. This even makes tons of tiny, threadlike strands that are very lethal to the touch. It will stick to skin, clothing, masks, weapons, vehicles. Horrible stuff. It stays for a very, very long time.

VX is a persistent agent. It is mainly used as an area denial weapon, like a minefield. Spray it and it will hang around as long as motor oil does. Again, this will kill people after the war is over.

Sulfur mustard (HD) freezes at 55°F. Spray it in a cold area, and it will not evaporate. It will stick to you if you walk through it, and when you get to a warm area, it will fuck you up.

Chem weapons hurt people who werent even around when they were being dropped. They kill non-combatants. They kill the next generation who was never at war.