In the previous chapter we studied the effect of weakened marital bonds on suicide. Of course, the family unit is only one of the entities to which an individual belongs. In the language of physical interactions, family bonds are short-range ties whereas links with society at large can be seen as long-range ties. Intermediate between short and long are medium-range ties with relatives, friends, neighbors, colleagues, etc. Typically, these links have a duration of a few years, whereas family ties have a duration of several decades.

A quick estimate of the strength of long-range ties can be obtained through the extreme value approach. It leads us to analyze the impact on suicides of major events such as the attack on Pearl Harbor and September 11, 2001. We will see that even such dramatic events have no visible effect on suicide rates. In the subsequent sections we consider various situations of social isolation such as illness, imprisonment or emigration. In each case the excess-suicides with respect to the general population can be taken as a proxy of the social ties which are missing or severed.

Effect of major historical events on suicide

First we examine the effect of the attack of September 11; then we discuss more briefly the consequences of the attack on Pearl Harbor.

September 11, 2001

In accordance with the extreme value approach we consider the number of suicides in the place where one may expect the effect to be greatest, namely in New York City. The series in Table 11.1a gives the monthly numbers of suicides in the three years 2000–2.