The mafia is a difficult industry to export, dependent on local conditions.

Evidence

Since it would be absurd to hypothesize that mafiosi did not export their industry because the North of Italy was less economically attractive than the South, it can only be concluded that the mafia is a difficult industry to export. Not unlike mining, it is heavily dependent on the local environment. Its initial costs can be met solely under a special combination of conditions since basic resources are expensive to produce in a void: information gathering and advertising, for instance, exploit independent networks of kinship, friendship, and ethnicity. Mafiosi active in the North of Italy were often there as a result of having been sentenced to obligatory confinement rather than of their own free choice (Sorbello 1983). Even the apparent exception of the U.S. mafia is misleading. Mafia families were not exported to America but emerged spontaneously, as it were, when the supply of and the demand for protection met: when, in other words, a sufficient number of emigrants moved there for independent reasons, some bringing along the necessary skills for organizing a protection market, and when certain events, notably the Great Depression and Prohibition, opened up a vast and lucrative market for this commodity. — Diego Gambetta, The Sicilian Mafia The Business of…, 665

Categorization

• XREF: Directly validates the reader’s Gambetta framework — the private-protection market emerges where supply and demand meet, echoing the Puzo/Corleone arc where American mafia was homegrown rather than imported.
• ADDENDUM: Connects to the reader’s ‘private protection markets’ frame — this is Gambetta’s own summary of why protection did not diffuse to the industrial North.