International security, the precondition of existence and development of international society, is also the focus of international
relations studies. There are many threats, both traditional and non-traditional, endangering
international security. The most serious among them are international terrorism, proliferation of weapons of mass destruction, and
hegemonism and power politics. As the Number one security threat to international society, international terrorism causes enormous trouble to every country, which forces people and governments to heighten their security awareness, adjust their security strategy, and enhance the security cooperation among international community. International society encounters considerable difficulties and obstacles in preventing the proliferation of weapons of mass destruction, namely, nuclear, biological, and chemical weapons, which constitutes another challenge to international security. As a traditional security threat but with a new face after Cold War, hegemonism and power politics remain the primary source of international and regional instability. They play the adverse role in weakening the role of the United Nations, upsetting global strategic stability, complicating regional affairs and giving impetus to international terrorism.