India, Sept. 1 -- The 81st anniversary of the bombing of Hiroshima passed on August 6 without many in India noticing. But Indians should be particularly concerned, and not just because the use of nuclear weapons has been threatened (implicitly, if not explicitly) one too many times in recent years. More importantly, the world today seems to tolerate the aggregate toll from ongoing wars, which could parallel the death and destruction from a nuclear attack.

Data on civilian casualties are mysteriously unavailable, and every theatre of war is seeing the use of conventional missiles. Suddenly, it is no longer clear where red lines lie for nuclear powers. This raises important questions about what constitutes deterrence for Indian security ag...