Attempting to simplify the crises in Syria by pointing at climate change seriously under states all other factors. Hell, one of your own links (the usda one) clearly shows that Syria has been able to meet its needs IF allowed via imports
The USDA link shows no such thing; it shows Syria eating up its reserves as it fails to import enough wheat to make up the shortfall. Yes, Assad underwrote the price of bread, but there wasn't enough subsidized bread to meet demand, forcing people to buy non-subsidized bread which increased in price six-fold. The net bread expenditure went up by 20% in a country where many people spend half their income on food.
I'm not a reductionist; situations like this have multiple important factors. The Assad/Islamist thing had been simmering for decades -- generations really. Had that situation been different, the climate shock might not have destabilized the country. In point of fact bread prices were an issue throughout the Middle East and a major factor in the Arab Spring. Syria was arguably better positioned than most other Arab countries, but the stress of having 5% of your population displaced on top of the deep and old fault lines broke the country apart.
This is precisely how climate shock is going to work. It won't be like the proverbial frog in a pot of boiling water; it'll be formerly rare occurrences happening more frequently and stressing vulnerable populations. Take sea level rise; cities won't drown slpowly, but what was once a hundred year flood will become twenty year flood. That will stress coastal cities, and the results depend on how stable and wealthy a particular city is.
For example were sea level to rise almost a meter by 2100 (as is now within the scope of mainstream positions), the very wealthy coastal city I live in would go the Venice route and build a tidal barrier, which would conservatively cost at least ten billion dollars. Chittagong Bengladesh, however, will be screwed. My city has twice the GDP of Bengladesh as a whole even though it has 3% of the population.