Part of an article written by Thom L.Jones,its about placing the italian mafiosi as mayors of towns after WWII...

AMGOT (Allied Military Government of Occupied Territories) commander Charles Poletti, was encouraged to recommend the re-placing of mayors into towns and villages as an urgent measure following the allied force’s occupation of Sicily. Many of these were also Mafioso. In fact, 90% of the 352 newly appointed mayors were either Mafioso or people linked into the Separatist movement which was inextricably allied to the Mafia.
While AMGOT was busy helping re-establish the Mafia, wittingly or otherwise, the OSS (forerunner to the CIA) had recognized the dangers inherent in this. Captain W.E. Scotton, early in 1944, produced a report on the Mafia presence in Sicily warning of ‘the signs of Mafia resurgence and its perils for social order and economic progress.’
The OSS had allied with the Mafia as part of the invasion strategy of the Allies in their assault on Sicily, and the agency kept close to them in order to check the growth of the Italian Communist Party on the island. There was also the very real danger that the Sicilian Separatist Movement, led by Finocchiaro Aprile, in alliance with the Mafia, would use the turbulent times to try to free itself from Italian hegemony.
Di Carlo was allegedly a captain in the US Marines who was assisting in this re-establishment exercise, and would have obviously supported Dr. Navarra who was in fact his cousin. It would have been a short step from backing a mayor to backing a new boss of the other side of Corleone. There is, however, doubt that Di Carlo was even in Sicily, as he was deported back to Italy sometime after 1947.