What character was used to make an atom bomb attack seem less dangerous

Bert the Turtle-Duck and Cover

The character was Bert the turtle.

Explanation:

Federal Civil Defense proposed an advertising campaing in 1952 called "Duck and Cover". The main character was the heroic Bert the turtle whose function in that educational/propaganda cartoon was to make an atomic bomb attack seem safer than it really was.

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he founded the house of wisdom to encourage arabic translation.

hope this is the right answer : ) : )