EU and US and Canadian Subsidies can't crush an Agricultural exporter, nor can sanctions.
Food is a required commodity, if they wanted they could just ban food imports and rely on their own food supply which wouldn't fear competition if you think thats the problem.
Sanctions stop new stuff from coming in, they don't stop food from being grown. You can't starve out a net food exporter with sanctions. The worst you could do is make them have warehouses of surplus food going to waste.
That isn't whats going on, So it would seem to be Mugabe.
Now, I will accept I may be wrong, perhaps dark beaver, rather than claiming victory in poorly spelled sentances, you could explain exactly how foreign powers did this to the food supply and their was nothing Mugabe could do to stop it, considering he can reposses peoples property and block imports on a whim.
Explain how, and maybe you won't come off as conceited , gullible, and ignorant. If you can't figure out a way this happens keep in mind, it doesn't mean your wrong. It means you shouldn't shoot your mouth off as if you know you are right, without being able to back up your statements.