A thing I would "uninvent"
If I were someone who had a power to uninvent something, I would definitely uninvent hydrogen bombs. Although, they are very important in a political arena and serve as a strategic leverage, they have to be destroyed in order to prevent any accidents in the future. Shall I remind you about the accident that happened in 1945 Japanese city "Hiroshima".
Many countries try to develop a hydrogen bombs and use them as a war weapons. They do not consider about the results that might have happen in case nuclear bombs will be utilized. Hiroshima and Chernobil accidents are very remarkable events; nevertheless, some countries still continue to explore a nuclear bombs.
For instance, one of the Central Asia's countries Iran has developed a nuclear bomb but nobody knows the real purpose of its invention. Also, they say that it was invented for scientific purposes, any country believes to that statement. Still, there are many hidden reasons why Iran had invented the hydrogen bomb and why they continue to affirm that it is only for scientific reasons.
Death of million people in Chernobyl and Hiroshima accidents do not stop countries to invent these nuclear bombs. I really do not know what could ever stop politicians from inventing something look like hydrogen bombs; moreover they have an experience with this kind of bombs.
Anyway, as I told you at the beginning that would be my thing I would uninvent in my life.