Perhaps you should refresh your knowledge of Uranium before implying that atomizing a lump of Uranium and spreading it around the globe would do harm. It WILL NOT!
On August 9, 1945, a quanity of plutonium that Ralph Nader has assured us was sufficient to kill everyone on the Earth at the time WAS released into the atmosphere.
And I guess the fears were justified. A large number of the people alive at that time are now dead, and most of the survivors are expected to die within a decade or so.