In Runaway Johnny, Mr. Black states that he destroyed a small island belonging to the country of Malaysia via explosives. The extent of this damage is unknown, as are the geopolitical effects. In particular, it is unknown whether any Malaysians or animal and plant life on the island at the time of the attack survived, to what extent the island's environment has recovered, and how Malaysia’s involvement in international affairs has shifted.
The U.S. government seems to have covered up Mr. Black’s involvement in the island's destruction. If it had not, one would expect him to be hunted across the globe by those outraged at the atrocity. Moreover, his lenient punishment suggests the U.S. government may have supported the attack for mysterious reasons. Indeed, it is possible that Mr. Black himself, feeling guilty over the attack, suggested he be temporarily reassigned to being a police officer, in which case it was not even a punishment from the government. It is unknown what the world at large thinks caused the destruction of the island.
To answer these questions, Johnny Test lore masters are hard at work searching for clues that may be scattered throughout the story or movie.