| If rank the events in 21th century by importance and influence, 9 ·11 must be on the top of the list. The tragedy's shadow is still in people's mind, even after years. At that time, terrorists hijacked airplanes to strike the Twin Towers in New York, which brought America and the world great damages at "zero cost". This event has changed the security concept of whole world, as well as the fundamental structure of international politics.Since the World War II, the terrorism has become more and more international and threaten the world peace and security. Along with the globalization of economy, the terrorism also gets some new characters. In such a globalization age, it is hardly imagine that a country can prevent terrorism alone. Only under the multilateral co-operational mechanism, we can effectively fight against terrorism. To build this co-operational mechanism, the UN must take its responsibility. As the biggest and most important inter-governmental organization, the UN has unique advantages. It should play a leading role in building counter-terrorism multilateral mechanism. As a multilateral platform, the UN has rich experiences in fighting against terrorism. Facing new security condition, the UN responses swiftly. It can combat terrorism with different weapons, such as law, organization, coordination and sanction.But the multilateral mechanism under the UN also encounters many challenges. Especially, the unilateral activity of US often marginalizes UN's authority. In international society, there are two different modes about counter-terrorism. The first one is led by US, and the other is by the UN. Though most countries agree that the UN should lead the fight, the UN has it own disadvantages: no army and no money. Facing challenges by US, the UN is hurt. After 9·11, US builded "willing coalition" to conquer Afghanistan; Less than two years, US invaded Iraq despite of the... |