Common grounds
No country needs another country. As no person needs another person. No interaction is mandatory. But it has a chance to be fulfilling and flourishing.
How about the global economy? We wove an international net of trade. We don't exchange potatoes straight to pineapples. There is a currency. We decided to use the dollar. The value of dollar is different for different people. Just as no one is valued the same by others. But there is an agreement among some major players. That oil should be traded around the world in US dollars. As everybody "needs" the oil, everybody "needs" the dollar. So it is a world currency.
When no one needs oil anymore, oil is depleted, or someone big breaks the agreement, there is a problem. Still somehow it works. World economy has its cycles. Sometimes it falls and then it rises again. A generation of people can experience a crash or 2 once in their life. So it is not something people are in constant fear of. Rather than a catastrophic event. Once we become a blind kittens treating money as a milk of life we fall into dismay. Is that something that we really want to tie our being with?
I'm pretty sure, I'll see a collapse of the global economy. To depend on such a system is ludicrous. But what can I do? We can not guarantee that everyone will need a certain currency across generations. And it turns out to be necessary for many people to see the collapse to realise, that money is not the reason of life. It is only the need for a single currency to trade at the moment. What are we going to use on Mars? May be there is something better than oil. No thing in life is constant.
Building own comforts. Self sufficiency. Connecting with like minded people. Those things become important. When the war starts, economy crashes, people get mad. There is probably no need in fixing anything in the current system. Everything is perfect anyway. I just wish I drive this vehicle smoothly.