Board Thread:Questions and Answers/@comment-1038387-20141010091035/@comment-1257201-20141010212425

He attacked the bomb that was heading for Kansas, and destroyed it using his own power and the power of the Shazam lightning, destroying himself in the process. (Btw, in the original KC I had the impression that many superheroes in Kansas survived the blast -- wasn't that the whole point of why he did it? -- but in the JSA sequel, the Earth-22 Superman believed all the heroes there had perished.)