  Game theory has been applied in many fields of study, especially economics
and political science. Arce M. and Sandler (2005) analyzed counter-terrorism
using non-cooperative game theory (the players are, for example, the US and the
EU), which assumes that communication among the players is not allowed, or, if
it is allowed, then there is no mechanism to enforce any agreement the players
may make. The only solution in the non-cooperative setting would be a Nash
equilibrium because the players adopt only self-enforcing strategies. Here we
analyze counter-terrorism using cooperative game theory, because there are ways
to communicate among the players and to make binding agreements; indeed,
countries that oppose terrorism are closely connected to each other in many
aspects such as economically and in terms of international politics.
