In a recent column, David Brooks 
(who is to applauded for often bringing social science research to his Times readers) argued that social policy has very limited effects on important human outcomes; it is “usually swamped by the influence of culture, ethnicity, psychology and a dozen other factors.”
The historical record, however, suggests that policy decisions often have quite profound consequences.
Brooks’s Case
Brooks largely rests his claim – that “most of the proposals we argue about so ferociously will have only marginal effects on how we live, especially compared with the ethnic, regional and social differences that we so studiously ignore” – on four observations: (a) the Swedish advantage over America in life expectancy has not changed since 1950; (b) Asian-Americans do consistently better educationally and in life spans than other American racial groups; (c) there are large regional differences in how well people do educationally and in longevity; and (d) statistical models suggest that increasing poor people’s income would not much change their life outcomes.
(Side notes: Brooks allows himself an out with the “most of the proposals” phrase. And I do not know who the “we” are in “the ethnic, regional and social differences that we so studiously ignore” – certainly the “we” cannot be sociologists.)
Brooks despairs that policy could have notable consequences. “When you try to account for life outcome differences this gigantic, you find yourself beyond narrow economic incentives and in the murky world of social capital. What matters are historical experiences, cultural attitudes, child-rearing practices, family formation patterns, expectations about the future, work ethics and the quality of social bonds.” (Interestingly, Brooks does not include in this list what many readers might – that genetic differences explain the life outcome differences.)
Far be it from a card-carrying sociologist like me to disagree that all those social factors matter. I will leave it to others to evaluate the four specifics (they are definitely more complex than suggested in the column). Here, I only want to note what we learn from history about the power of policy.
Policy History
Here are four examples where we can reasonably conclude that policy decisions had major, fateful consequences (and, by the way, I’ll ignore other, more obvious policy decisions, like going to war, the end of Reconstruction, the Voting Rights Act, and such).
Longevity: This is an example I have used before, but for the record: the construction of public water and sewage systems about a century ago, coupled with government regulation of food, was responsible for the single-greatest extension of Americans’ life spans.
Affluent Longevity: It was not only the development of Social Security, but critically, also the establishment of automatic cost-of-living adjustments for Social Security – something the Congress purposely chose not do for the minimum wage – 
that largely account for why poverty among the elderly plummeted since 1960, so that the elderly became less poor, on average, than the non-elderly. (An excellent study of the various ways government insured Americans’ security is a book by David Moss.)
Switching Immigration Flows: In the early 1920s, the U.S. effectively closed the door on immigration from much of Europe, changing the complexion of the United States for decades to come. In 1965, the U.S. re-opened the door and one policy in particular – a policy that consequences of which were unintended, family reunification – led to a huge flow of immigrants from Asia and Latin America, again changing the complexion of the United States for decades to come.
More Inequality: Economic inequality has been widening for 40 years after prior decades of narrowing. Because this has happened in other western nations, some observers have explained it as a global inevitability outside the control of policy makers. However, inequality shrank in a few countries and stayed moderate in others. American policies – for example, minimal intervention in wage-setting labor markets, minimal redistribution of taxes, minimal universal provisions (like health care), and deciding not to adjust the minimum wage for inflation – have made America the western world’s leader in inequality (see Inequality by Design).
Closing Comment
It is often difficult to establish statistically that a particular event made the difference in a general trend. (For example, some analysts argue that the economic fortunes of the elderly were generally improving with or without the original Social Security Act.) But in these examples, the changes and the differences are sufficiently stark that it is hard to argue that policy decisions did not have major consequences.
Brooks’s conclusion, that “most of the proposals we argue about so ferociously will have only marginal effects on how we live,” is hedged. But in reality many of the past proposals we have argued about – and some we perhaps have not argued about as much as we should have – still have serious effects on how we live.
