Despite the balance of terror why did people still fear nuclear war

Given the "risk balance" why were people always afraid of nuclear war? ... It led all superpowers to avoid launching a nuclear attack because if one side launched a nuclear attack, the other side would retaliate, destroying all sides.

Explanation: i believe that people fear nukes is because the impact of the explosion and sound makes a massive impact to the civilization.

worldwide, 780 million people do not have access to an improved water source. an estimated 2.5 billion people lack access to improved sanitation (more than 35% of the world's population)

i believe it to be a democracy