A Dystopian Future?

I tend to be a pretty optimistic person, I think.  But after reading quite a few popular young adult novels as well as my husband's Analog science fiction magazine, I'm wondering if my optimism is perhaps naivete or even willful blindness.  There are a couple of disturbing themes that arise from many of the books that I've picked up - first is the utter disappearance of the United States as a country and the structures that support its society; second is the caste-like hierarchies that have evolved to support the unique societies. In the Divergent series, at least there is some element of choice for most of the characters when becoming part of the societal groups. In The Selection, the characters are born into their castes - and they can move up in the caste, but there are specific qualifications that have to be met.

So, why the grim prediction of our future?  It is true that much young adult literature has a tendency to be dark; perhaps this reflects the struggle for young people of anticipating the future and a lack of control...perhaps it is a reflection of the current economic uncertainties.  I'm not sure of any answer, but I'll work on keeping my optimistic attitude while enjoying the strong women characters who emerge.