分类：教育/科学-外语学习
问题：请问这个calculus是什么意思请问在下边这句话里calcul 
请问在下边这句话里calculus是什么意思？The events of September 11,2001, signal an inflection point between the remnants of the security environment dominated by the symmetrical calculus of the Cold War and the uncertainties and asymmetries of the 21st century security environment.最好是帮我把这句话也翻译请问在下边这句话里calculus是什么意思？The events of September 11,2001, signal an inflection point between the remnants of the security environment dominated by the symmetrical calculus of the Cold War and the uncertainties and asymmetries of the 21st century security environment.最好是帮我把这句话也翻译一下，多谢了
回答：2001年的911事件标志着（国际）安全环境由冷战中（美苏）双方所控制的势均力敌向21世纪的不确定性和非对称性的转折。

calculus本意是“结石”。“对称的结石”指美苏双方势均力敌