ccg, many good points. And you might be right about Europe, but I suspect they may be more resilient than we give them credit for.
As to hoarding, it is kind of in the eyes of the beholder--when is it hoarding and when is it 'prudent build of food stocks in the anticipation of coming shortages'?
It seems to me that if most countries had a reliable back-up supply of grains and some other relatively non-perishable food stuffs, that would make it less likely that there would be local and regional food shocks.
"America should enjoy a position of relative privilege"
Again, privileged Americans should enjoy a position of relative privilege. Most of the rest of us are a few paychecks from homelessness and food insecurity (if we aren't already there as are about 50 million so far). And, perhaps you haven't noticed, but we've become much more of a police state since 9/11. All urban police forces have been greatly militarized, especially with training in crowd control/suppression of varying levels of brutality. ('oogle 'food insecurity' and 'militarization' for more info on these subjects than you'll know what to do with.)
But yes, between having a military larger than the next ten largest militaries combined (at least by expense), and having some of the world's most productive crop lands, we have some advantages. But these are also more and more undermined by enormous debt, political incompetence, and failures on a number of other fronts.
(I honestly can't parse sentences like: "Surrender or be tortured and die, became surrender and some of you will be tortured and die was a reality of our ancient past, when men lost honour." If others think they can, they are more than welcome to address whatever point was trying to be made there.)
On the China thing, I obviously was not talking about military invasion, but that there was concern that they were planning to buy up rights to basic water supplies in the midwest. As the US and other western colonial powers have long learned, you don't always have to use direct military force to take over a country's resources--economic 'force' will often do just fine.
But as to their history of non-invasion, the Tibetans, Uyghurs and a number of other historically non-Han nationalities might disagree with that math. Of course, once you've been invaded and redefined as part of China, the Chinese are eager to have you and everyone else forget that you didn't join the empire completely willingly. But perhaps a tour of 3000+ years of Chinese history would take us a bit far afield from the main topic of the thread?
Mostly, China has done an amazing job of feeding about 20% of the world's population on about 9% of the world's arable land mostly without importing massive quantities of food (as my bro points out in one of the articles in the last source I cited--didn't even notice he had something in there till after I posted the link).
But a couple bad years there (in India, in Russia...) and they will be out buying up as much food on the global market as they can, and they have a lot of US $$$ to buy it with.
To circle back and connect all this to "CC, the ocean, ag, and food," one predicted outcome of even one degree of GW (or less) is the destabilization of the Nebraska (and other) Sand Hills. During the thermal optimum earlier in the Holocene, these were Sahara like dunes that blew around the great plains making unimpeded. Over the last few millennia, they have been mostly stabilized by deep rooted grasses that wetter, cooler conditions have allowed to thrive there. But the long drought that still has its grip on that region will eventually be too much even for those hearty grasses to endure, and enormous hills of sand will again start to migrate across some of the most productive land in the world, turning fields into deserts. Some of the conservation measures that were put in place since the dust bowl days will doubtless help slow some of that. But even those tree breaks won't be much of a match for hills of sand. And of course many of those tree breaks have been bulldozed or are succumbing themselves to the area's perma-drought.
And then we still have the collapse of the Hadley Cell system due to the opening of the Arctic Ocean (see I got ocean in there, too
). Does anyone really think that a major re-distribution of where rain falls when and how much, in the Northern Hemisphere will
not cause a major...disruption of world agriculture and fundamentally challenge humanity's ability to feed itself?
These are among the kinds of 'discontinuities' that make it unlikely that we will merely see a gradual decrease of 2, 4 or any other consistent percentage.