I'm thinking life will go on much as it always has. Unlike many other countries, the United States mediates change pretty well, mainly because we have a consensus-based system in which 50% plus 1 means you get to do what you want.
As for the moral trajectory of the country, it's always followed a sine wave or a spiral between laxity and rigor. We bottomed out on laxity about a decade ago, and are returning more to the middle. In a decade, this will be a much more socially conservative country than it is today. That's more or less inevitable, since it is the socially conservative who are reproducing, and, one assumes, passing their values on to their progeny, who in turn will also reproduce themselves with change to spare.
Look at Jews for the situation in microcosm: Reform Jews, who make up the majority of Jews in America, are politically and socially liberal; they have, on the average, fewer than two children; they tend to marry outside of Judaism about half the time; and the children of those mixed marriages tend to leave Judaism about half the time. So, do the math: 1.5 x .5 x.5 =0.375. Every Reformed Jewish couple ends up passing a third of a Reformed Jew to the next generation. In three generations, they will cease to exist.
Orthodox Jews, on the other hand, make up a small proportion of the Jewish population (about 15%), but they tend to have four or more children, and those children overwhelmingly marry other Orthodox Jews, and their children are raised as Orthodox Jews as well. Assume three of four Orthodox Jewish children remain within the Orthodox fold. Then you get 4 x .75 =3.0. Every Orthodox Jewish couple pass down three Orthodox children to the next generation, which results in a 50% growth rate (and I'm being conservative here). So, within a generation or so, Orthodox Jews will outnumber Reformed Jews, and the moral, social and political outlook of the Jewish community will change.
It is the same among Christians: those who actually attend Church regularly tend to be much more politically and socially conservative, and to have more children than those who are only nominal or casual Christians. Demography is destiny. In a few generations, young people will look back on their grandparents' generation as being both foolish and depraved. That the Baby Boomers will have spent their grandchildren's inheritance will only make the reaction of the young even stronger.
