This essay contextualizes what we understand by US unilateralism by referring to the current order of international society whose primary interests is in security. In such an overall context, the essay seeks to explain the reason why the US rejects the International Criminal Court while European countries strongly support it. Then the essay identifies two globalizations and two realisms: US led universalistic globalization and Europe led multilateral globalization, and realism as power politics which emphasizes the role of great powers and realism as statism which emphasizes independence and equality of states.