hence i say chemical warefare is the most effective. There are many chemicals that can be used. Their applications and methodology are myriad. LSD is my favorite because it requires relatively little material, has a devestating effect that will last for at least a day, and will cause immediate devestation. It also racimates after a fairly short time and is not fatal if you know what it is. It would also cause enough havoc to leave behind only a small group of people that would pose no real threat when you moved in to secure the nation. Additionally, there is currently no way to terminate the trip and there is no vaccine for it. plus, lsd would be hard to blame on an enemy government as it could just as easily come from someone trying to make it in a lab who got nervous about being caught and simply flushed it.lol.