2 - is a little pedantic, they used agent orange to kill foliage to kill people...
They didn't gas people with chlorine or mustard, but they mass destroyed crops and foliage, to kill people.
And "affected US troops as much as Vietnamese" is just completely incorrect, US covered a nation in herbicide, went home, got cancer. Is completely different then having your soil destroyed for decades.
"Can be used as a weapon" applies to nearly everything, and ceases to have any meaning. Even on a tank, they aren't considered a weapon, only the whole take together is the weapon, or the cannon alone.
They didn't gas people with chlorine or mustard, but they mass destroyed crops and foliage, to kill people.
And "affected US troops as much as Vietnamese" is just completely incorrect, US covered a nation in herbicide, went home, got cancer. Is completely different then having your soil destroyed for decades.