Answer:
The Russians did not react to the warning of the US.
Explanation:
The United States wanted the Soviet Union to know that America had this capability. During world war I, the two emerging powers were the United States of America and the Soviet Union.
United States wanted to show the Soviet Union its power and capability of how it can be a powerful nation and threatened to destroy Japan by striking with more power and weapons from the sky, land and sea and would destroy Japan in such a way that humanity has not seen such destruction earlier.
So the US warned them that if Japan did not accept the terms of America it would drop atomic bomb on it and would destroy and killed Japanese people.