Some arguments are hard to settle but are too important to avoid. Here's one: whether the social crisis among America's poor and working class - the collapse of the two-parent family, the weakening of communal ties - is best understood as a problem of economics or of culture.
This argument recurs whenever there's a compelling depiction of that crisis. In 2012, the catalyst was Charles Murray's "Coming Apart", with its portrait of the post-1960s divide between two fictional communities - upper-class Belmont and blue-collar Fishtown. Now it's Robert Putnam's Our Kids, which uses the author's Ohio hometown to trace the divergent fortunes of its better-educated and less-educated families.
Murray belongs to the libertarian right, Putnam to the communitarian left, so Putnam is more hopeful that economic policy can address the problems he describes. But Our Kids is attuned to culture's feedback loops, and it offers grist for social conservatives who suspect it would take a cultural counter-revolution to bring back the stable working class families of an earlier America.
That idea makes some people on the left angry. As they see it, it's money and only money that Murray's Fishtown and Putnam's hometown lack and need. It's unchecked capitalism and Republican stinginess, not the sexual revolution, that has devastated working-class society over the last decades. Fight poverty, redistribute wealth, and you'll revive family and community; it's that simple.
Their argument gets some things right. The United States economy is not performing as well as it once did for less-skilled workers. Certain regions - like Putnam's Ohio - have suffered painfully from deindustrialisation. The shift to a service economy favoured women but left low-skilled men less marriageable. The unions' decline has weakened professional stability and bargaining power for some workers.
And yet, for all these disturbances and shifts, lower-income Americans have more money, experience less poverty, and receive far more safety-net support than their grandparents ever did. Overall, material conditions have improved across the period when their communities came apart.
Between 1979 and 2010, for instance, the average after-tax income for the poorest quintile of US households rose from US$14,800 to US$19,200; for the second-poorest quintile, it rose from US$29,900 to US$39,100.
Meanwhile, per-person anti-poverty spending at the state and federal level increased sixfold between 1968 and 2008 - that's excluding Medicare, unemployment benefits and Social Security.
Despite some conservative scepticism, this spending did reduce the poverty rate (though probably more so after welfare reform). One plausible estimate suggests the rate fell from 26 per cent in 1967 to 15 per cent in 2012, and child poverty fell as well.
These trends simply do not match the left-wing depiction of a working class devastated by Reagonomics. Nor does the long-term trend in insurance coverage, or per-student spending, or other data. The left sometimes claims that the income instability of working Americans is unprecedented, for instance - but a 2007 Congressional Budget Office estimate found "little change in earnings variability" over the preceding decades.
This is a dense debate whose surface I can only skim. (Inequality as well as absolute income enters into it, as do immigration, cost inflation for key goods - including weddings! - and more.)
But the basic point is this: In a substantially poorer American past with a much thinner safety net, lower-income Americans found a way to cultivate monogamy, fidelity, sobriety and thrift to an extent that they have not in our richer, higher-spending present. So however much money matters, something else is clearly going on.
The post-1960s cultural revolution is not the only possible "something else". But when you have a cultural earthquake that makes society dramatically more permissive and you subsequently get dramatic social fragmentation among vulnerable populations, denying that there is any connection looks a lot like denying the nose in front of your face.
But recognising that culture shapes behaviour and that moral frameworks matter does not require thundering denunciations of the moral choices of the poor.
Instead, our upper class should be judged first - for being too solipsistic to recognise that its present ideal of "safe" permissiveness works (sort of) only for the privileged, and for failing to take any moral responsibility (in the schools it runs, the mass entertainments it produces, the social agenda it favours) for the effects of permissiveness on the less-savvy, the less protected, the kids who do not have helicopter parents turning off the television or firewalling the porn.
This judgment would echo Leonard Cohen: "Now you can say that I've grown bitter but of this you may be sure / The rich have got their channels in the bedrooms of the poor."
And without dismissing money's impact on the social fabric, it would raise the possibility that what's on those channels sometimes matters more.
NEW YORK TIMES