When I'm 121

If the United States was sustainable in 100 years I imagine a severe population decrease.  I know that many people in my generation aren't planning to have children for environmental reasons. And instead of a highly advanced technological society I imagine we go back to our roots of living off the land. I imagine most people to have their own sustainable communities where they grow their own food and raise their own livestock, where trading amongst neighbors is the norm and large superstores don't exist. I imagine that some people drive cars (hopefully fully electric) but bicycles and other forms of public transportation are used more regularly. Clean drinking water will become tricky seeing that fresh water is already a scarce resource. But the United States has a fairly large amount of fresh water and I see it being evening distributed across the country. The problem with this view is that it alters the United States into a seemingly utopian society. The odds of this country returning to an agricultural state of being is incredibly slim. But I don't think technology (even green technology) is really the answer.  I believe that in order to be completely sustainable individuals have to take charge of their own food and production and they have to learn to live off the land. Once again I don't see this happening in our country but I do hope that when I'm 121 (hopefully I won't be alive) that our economy and lifestyle depend on the land and we don't take it for granted.