We live today in a world of information and communications technology. For all the wonders it can work, it is actually quite fragile, dependent on a whole host of things to ensure it operates smoothly.
One of those things is batteries. However brainy and communicative your latest laptop may be, it is not worth the paper it prints on if it happens to be running on batteries and those batteries are about to go dead.
There is another very important aspect of today's world that is also running on batteries. That is the United States economy. Its finances are not plugged into an independent energy source. The economy's huge current account deficit is being sustained by financial batteries that are of foreign manufacture.