Hello Priscilla, To answer your question I would offer you this definition of 'calculus' from MIT: "Calculus is the study of how things change. It provides a framework for modeling systems in which there is change, and a way to deduce the predictions of such models." So, 'national calculus' might mean the normal ordering and way of doing things for a particular society. So it is the way that a society normally runs and can be expected to run and to function. A terrorist attack is a serious shock to such a system, hence the use of 'scrambled' I hope this is interesting/helpful! Best wishes, Richard

In this context, it refers to the calculation or strategy used. After a terrorist attack a country may have to quickly change their strategy regarding national security. Or a politician may need to recalculate the effectiveness of a campaign's messaging.

Normally, calculus refers to a type of calculation or methodology, but in this case, in the case of "the national calculus" or "political calculus", it is closer to "agenda", "plan", or "expectation." In any case, this is a very formal usage and not very commonly seen. It's only used occasionally in academic papers or reputable news sources. Certainly not something that you encounter in a daily conversation with a friend.

i believe that the term calculus is being used as an umbrella term for statistics in general. terrorist attacks affected national statistics in an erratic way for example. and political calculus could mean the embellishment/manipulation of political statistics? i'm not sure but that would be my guess. Hope this helps