  A model to describe the spontaneous formation of military and economic
coalitions among a group of countries is proposed using spin glass theory.
Between each couple of countries, there exists a bond exchange coupling which
is either zero, cooperative or conflicting. It depends on their common history,
specific nature, and cannot be varied. Then, given a frozen random bond
distribution, coalitions are found to spontaneously form. However they are also
unstable making the system very disordered. Countries shift coalitions all the
time. Only the setting of macro extra national coalition are shown to stabilize
alliances among countries. The model gives new light on the recent
instabilities produced in Eastern Europe by the Warsow pact dissolution at odd
to the previous communist stability. Current European stability is also
discussed with respect to the European Union construction.
