The Paschal Triduum, or the Three Days.
Such melding of different peoples is a kind of Ethnogenesis. Ethnogenesis (from the Greek “<em>ethnos</em>”-people- and “<em>genesis</em>” -origin-) is a process by which a group of people is gathered to form a new ethnic group. These people may be ethnically associated with the new group or be outsiders who self-identify with the values/thoughts/ideas of the new group.
More specifically, this particular example is Passive Ethnogenesis, because people come together in a group that creates cultural-identity relationships, in this case being fans of the national football team.
The answer is "Drug Enforcement".
Plain folks, hope this helps.