What do these crises have in common:
Okay, they probably have lots of things in common. But the answer I was looking for is "food."
Imagine for a minute that everyone in the United States stopped overeating and became vegetarians, perhaps with some fish thrown in the mix for protein and Omega-3. We all know that situation can never happen, so this is just a thought experiment.
Healthy eating would have a huge impact on healthcare costs. It would be partially offset by people living longer, but I have to think multiple sports injuries cost less than one heart bypass operation. And I read somewhere that 40% of mortgage foreclosures are caused by health problems. (Anyone have a link for that?) So in the short run, until the world is overrun by 200-year old marathoners collecting Social Security, the economy would be better off if people ate right. And that would free up money to insure the uninsured.
Now imagine that cattle are taken out of the food chain. Suddenly you don't need to cut down the rain forests to create new pastures, and the cost of food would drop because veggies are much cheaper than cows. Preserving trees would help the environment, which is also good for the economy. Beef suppliers wouldn't be too happy about this situation, so that is one offset to consider. But your food bill would be substantially lower.
Two-thirds of the world's fresh water supply goes to agriculture, and some sources claim that half of that water is wasted because of inefficient irrigation methods. Once again, food is the culprit. If we irrigated more efficiently we'd have plenty of water.
Now consider how much energy is expended in the pursuit of food. The typical American eats twice as many calories as needed. And most families are making multiple car trips to the grocery store, or to get take-out, every week. If we cut our calories in half, we could enjoy more leftovers and reduce all the driving we do for food. Plus we'd weigh less, so our cars would use less fuel hauling us around.
Therefore, food-related inefficiency is a big contributor to most other crises. Unfortunately, food is somewhat sacred, so political solutions around food are not practical. And our cigarette-smoking President isn't in a position to tell people they should eat less. So don't expect anything to change.