A disagreement about the positive impacts of immigration and diversity has emerged between Robert Putnam, the distinguished Peter and Isabel Malkin Professor of Public Policy at Harvard University, and Mark Krikorian, the Executive Director of the Center for Immigration Studies. 
The disagreement started with a Wall Street Journal article by Krikorian that was the subject of a prior post although that post did not emphasize one of the article’s points that has given rise to this disagreement. Krikorian argued that immigration will overwhelm American culture by stating the following:
- “[H]igh levels of immigration actually exacerbate the bowling-alone tendencies in the wider society, overloading it with ethnic diversity than it cannot handle. It is not that diversity causes increased hostility between groups, as one might expect. Rather, it causes people to disappear into their shells like turtles.”
As support for this assertion, Krikorian cited Putnam’s article—E Pluribus Unum: Diversity and Community in the Twenty-first Century (The 2006 Johan Skytte Prize Lecture), Wiley Online Library (June 15, 2007).
In addition, Krikorian as additional support for his argument quoted the following from the Putnam article: “Inhabitants of diverse communities tend to withdraw from collective life, to distrust their neighbors, regardless of the color of their skin, to withdraw even from close friends, to expect the worst from their community and its leaders, to volunteer less, give less to charity and work on community projects less often, to register to vote less, to agitate for social reform more but to have less faith that they can actually make a difference, and to huddle unhappily in front of the television.”
Another quotation from Professor Putnam is also found in the Krikorian article: immigration has made Los Angeles into ‘”among the most ethnically diverse human habitations in history’ and had the lowest level of social trust among all the communities that his team studied.”
Professor Putnam, however, has taken exception to this use of his article, which, he correctly says, provided “empirical evidence for [the following] three major points:
“1. Increased immigration and diversity are not only inevitable, but over the long run they are also desirable. Ethnic diversity is, on balance, an important social asset, as the history of the U.S. demonstrates.”
“2. In the short to medium run, however, immigration and ethnic diversity challenge social solidarity and inhibit social capital.”
“3. In the medium to long run, on the other hand, successful immigrant societies like the U.S. create new forms of social solidarity and dampen the negative effects of diversity by constructing new, more encompassing identities.”
According to Putnam, Krikorian “cherry-picks the middle point but entirely ignores the first and last because they are inconvenient for his policy recommendations. . . . In my 2007 article, I specifically warned against this danger: ‘It would be unfortunate if a politically correct progressivism were to deny the reality of the challenge to social solidarity posed by diversity. It would be equally unfortunate if an ahistorical and ethnocentric conservatism were to deny that addressing that challenge is both feasible and desirable.’ Mr. Krikorian’s tendentious use of my research illustrates precisely how our civic culture, which he claims to value, is being undermined in today’s public dialogue.”
Professor Putnam’s article also concludes with this statement: “One great achievement of human civilization is our ability to redraw more inclusive lines of social identity. The motto on the Great Seal of the United States (and on our dollar bill) and the title of this essay –e pluribus unum– reflects precisely that objective – namely to create a novel ‘one’ out of a diverse ‘many’.”
As an advocate for U.S. immigration, I naturally side with Professor Putnam on this debate. Several other thoughts come to mind. If God created human beings as clones, what a boring world this would be. The social world is always changing. As was said many years ago by the Greek philosopher Heraclitus, who was famous for his insistence on ever-present change as being the fundamental essence of the universe: “No man ever steps in the same river twice.” On the other hand, I also believe there is wisdom in skepticism of grand theories and in favoring incremental, as opposed to revolutionary, change.
 Professor Putnam also is a member of the National Academy of Sciences and the British Academy; past president of the American Political Science Association; recipient of the Skytte Prize, the most prestigious global award in political science; and recipient of the National Humanities Medal, the nation’s highest honor for contributions to the humanities.