Building on the work of the criminologist Gary LaFree, Roth argues that two related factors correlate most heavily to the murder rate: 'the proportion of adults who say they trust their government to do the right thing and the proportion who believe that most public officials are honest' (p. 17). In essence, the less faith Americans have in their government, the more likely they are to commit murder. For instance, the murder rate declined significantly during Franklin D. Roosevelt's presidency, when Americans had significant faith in government, only to have the murder rate rebound in the sixties and seventies because of unrest brought about by the civil rights movement, the Vietnam War, and Watergate.
The rest of Sikenat's review questions Roth's methodology and the accuracy of his homicide statistics without comment on the LaFree thesis on which Roth's argument appears to depend. LaFree's book Losing Legitimacy is available online as a Google Book; here is a relevant chapter that clarifies his view on trust or faith in government. Taken at third hand, LaFree's finding could be interpreted to attribute murderous tendencies to an ideological lack of faith in government, such as expressed by many American reactionaries today. Skimming over LaFree's actual writing tells a somewhat different story. He argues that homicide (if not all violent crime) increases due to loss of faith in government, as in the Sixties, but isn't necessarily influenced by lack of faith. In any event, LaFree attempts to correlate homicide rates with very broad public-opinion surveys, which is to say that, at most, American murderousness might be correlated with the level of anti-government sentiment, though not necessarily anti-government sentiment itself. It also seems that you're more likely to kill, based on LaFree's research, if you think that government isn't doing something it's supposed to than if you think government is doing something it shouldn't.
It's unclear whether LaFree or Roth goes on to compare the American stats with those for other affluent democracies. It is clear, however, that LaFree, at least, is writing about street crime, not the amoklauf that is still largely an American phenomenon. Nevertheless, theirs is a disturbing suggestion that ought to be researched further. Americans have, arguably, a more complicated relationship to government as a concept and as a fact, and on emotional and psychological as well as legal levels, than people of other lands. If that argument can be proven, and a link between that relationship and criminal impulses confirmed, it might say something damning about the American experiment or what's become of it.