[cma]

I don't disagree with you, but you can take it further: what if someone is growing potatoes, some of which go to feed weapons systems (troops)?

[jaekwon]

that would make you a potato farmer.

[natrius]

I don't know what international law says, but I'd destroy the crops and leave the farmer alone.

[cma]

Didn't work so well the last time we tried it: http://viartis.net/parkinsons.disease/images/AgentOrange.jpg