Whites are particularly gloomy: Only 1 in 6 expects better times over the next four decades. Also notably pessimistic are middle-age and older people, those who earn mid-level incomes and Protestants, a new national poll finds.
"I really worry about my grandchildren, I do," says 74-year-old Penny Trusty of Rockville, Maryland, a retired software designer and grandmother of five.
"I worry about the lowering of morals and the corruption and the confusion that's just raining down on them."
Even groups with comparatively sunny outlooks racial and ethnic minorities, the young and the nonreligious are much more likely to say things will be the same or get worse than to predict a brighter future.
"Changes will come, and some of them are scary," says Kelly Miller, 22, a freshly minted University of Minnesota sports management grad.
She looks forward to some wonderful things, like 3D printers creating organs for transplant patients. But Miller envisions Americans in 2050 blindly relying on robots and technology for everything from cooking dinner to managing their money.
"It's taking away our free choice and human thought," she says. "And there's potential for government to control and regulate what this artificial intelligence thinks."
Overall, 54 percent of those surveyed expect American life to go downhill, while 23 percent think it will improve, according to a December survey from the AP-NORC Centre for Public Affairs Research.
Only 21 percent predict life will stay about the same. That minority may be onto something, however.
While no one can say what catastrophes or human triumphs are to come, contentment at a personal level has proven remarkably stable over the past four decades.
Interviews by the federally funded General Social Survey, one of the nation's longest-running surveys of social trends, show Americans' overall happiness as well as satisfaction with their jobs and marriages barely fluctuating since 1972.
Those decades spanned the sexual revolution and the women's rights movement, race riots and civil rights advances, wars from Vietnam through Afghanistan, the birth of the home computer and the smart phone, boom times and hard times.
Despite the recent shift toward negativity, the portion of US residents rating themselves very or pretty happy stayed around 9 out of 10.