In early 2001 the Taliban banned the growth of poppies and opium export plummeted to near zero.

>The first American narcotics experts to go to Afghanistan under Taliban rule have concluded that the movement's ban on opium-poppy cultivation appears to have wiped out the world's largest crop in less than a year, officials said today. The American findings confirm earlier reports from the United Nations drug control program that Afghanistan, which supplied about three-quarters of the world's opium and most of the heroin reaching Europe, had ended poppy planting in one season.

>But the eradication of poppies has come at a terrible cost to farming families, and experts say it will not be known until the fall planting season begins whether the Taliban can continue to enforce it.

https://www.nytimes.com/2001/05/20/world/taliban-s-ban-on-po...

Later that year America invaded and poppy production soon exceeded historic numbers by a significant margin.

https://en.wikipedia.org/wiki/Opium_production_in_Afghanista...

Make of this what you will.

Spraying would be effective at destroying poppies in Afghanistan. There's nothing technical stopping poppies from being eradicated in Afghanistan, it's political more than anything. Opium cultivation in Afghanistan has been tolerated by the US and Afghan governments for a variety of reasons.

The USA discovered in the Vietnam War that destroying people's livelihood isn't a great way to win hearts and minds. Unfortunately half of Afghanistan's GDP comes from opium and heroin.

The Afghan government doesn't want to eradicate opium production because half of the government is involved in the opium trade.

The Russians actually wanted to spray the fields back in 2010, but the USA declined [1].

ISAF actually specifically avoided destroying poppy fields, if you watch documentaries from the Afghan War, like Restrepo or The Battle for Marjah, you'll see American troops just walking right through poppy fields and doing nothing.

[1] https://www.reuters.com/article/uk-nato-russia-afghanistan/n...

It'd be a lot easier to make cheap, pure heroin available to people who choose to use it. Switzerland does just that and it seems to benefit their society while taking money out of the pockets of the drug cartels: http://drugwarfacts.org/region/switzerland

It's a big mixed bag. If you do it that way, you just massively increased the recruitment potential for the Taliban. All of those farmers are now wiped out, have nothing to do for work, and have a new sworn enemy for life. The only possible solution that might yield positive results is aggressive replacement subsidization (extremely expensive).

I would consider it biological warfare, which is banned.