Since the end of the Cold War, humanity's wealth has come from the sheer number of cultures. Power is seized through the domination of minds, counter-culture and the subtle mechanisms of diplomatic power revealed by cultural influence. The "soft power" in which symbolic hegemony counts as much in the balance of power as the classic material determinants (population, army, economy). It's the ability to shape the preferences of others, to seductively structure the messages of the world of diplomatic relations as a factor of power and domination. It is a state's hegemonic power, representing a power of seduction, a power of co-optation that enables its holder to incite other actors to imitate it. The book defines the very concept of culture, the different analyses and approaches of the theories of international relations in the field of culture, and discusses the different state and non-state actors. Cultural diplomacy is not forgotten, as we look at geopolitics, globalization and terrorism from a cultural perspective.