Suppose a major city (London, Paris, New York, etc.) is attacked in a major "conventional" war nowadays. How would defense be handled?

by [deleted]
depanneur

Sorry, but your submission has been removed because we don't allow hypothetical questions. If possible, please feel free to rephrase the question so that it does not call for such speculation, and resubmit Otherwise, this sort of thing is better suited for /r/HistoryWhatIf.