David Brooks thinks Americans - in particular, less educated, less affluent Americans - are losing their morality. He blames this on the death of collectively enforced social norms:

We now have multiple generations of people caught in recurring feedback loops of economic stress and family breakdown, often leading to something approaching an anarchy of the intimate life...It’s not only money and better policy that are missing in these circles; it’s norms...In many parts of America there are no minimally agreed upon standards for what it means to be a father. There are no basic codes and rules woven into daily life, which people can absorb unconsciously and follow automatically...These norms weren’t destroyed because of people with bad values. They were destroyed by a plague of nonjudgmentalism, which refused to assert that one way of behaving was better than another. People got out of the habit of setting standards or understanding how they were set.

I think David Brooks should look at the statistics on American behavior.

• Crime is way down and continues to fall.

• Teen drug and alcohol abuse is way down and continues to fall. 

• Teen pregnancy is way down and continues to fall.

• Domestic violence is way down and continues to fall.

• Child molestation is way down and continues to fall.

In other words, Americans are becoming better and better behaved in almost every way. 
So David Brooks is cooking up off-the-cuff sociological theories to explain SOMETHING THAT ISN'T EVEN HAPPENING. And then he is recommending big changes in American culture and society, based on his off-the-cuff sociological explanation for SOMETHING THAT ISN'T EVEN HAPPENING.
(So of course we also don't need to invoke poverty to explain the nonexistent "increase in bad behavior"!) 
Yes, Americans - especially lower-class Americans - are suffering from family breakdown and social isolation. These seem like problems of loneliness, not of loss of morality. They're obviously not leading to increases in violence or drug abuse.
You see, the problem with being a grumpy old guy scanning the media for negative anecdotes and grumbling about the world going to hell in a handbasket, and how the only solution is to somehow revamp society to bring back old social norms is that someone might actually listen to what you say.