You think those countries, besides the US, have a strong agriculture? Hell, China has a whole science dedicated to making it's dead and useless soil grow plants. Well I guess we could all eat rice.
The grain feed you speak of is not consumed by vegans. It's highly modified so it can be grown quickly and cheaply to feed the beef and poultry. If you wish to replace the animals with the equivalent volume in vegan food, the grain feed that goes to them is not going to help (unless the vegans alter the "guns" they stick to, but then we're back to square one). Even replacing cattle farms with vegetable fields isn't going to be enough, you'd have to expand (so this is AFTER all cows, chickens and pigs have died).
The grain feed you speak of is not consumed by vegans. It's highly modified so it can be grown quickly and cheaply to feed the beef and poultry. If you wish to replace the animals with the equivalent volume in vegan food, the grain feed that goes to them is not going to help (unless the vegans alter the "guns" they stick to, but then we're back to square one). Even replacing cattle farms with vegetable fields isn't going to be enough, you'd have to expand (so this is AFTER all cows, chickens and pigs have died).
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