It is illegal for private individuals to prepare bombs of any type. But countries can do what they want to.
Ownership of highly enriched Uranium, Uranium-233, or Plutonium by private individuals is illegal in the US and probably several other countries. Without one or the other no nuclear bomb can be built.
No, China has several hundred nuclear bombs and has had bombs since 1964.
they mostly not
Nuclear bombs are illegal since bombs could potentially be harmful to others and places, so no it is not legal.
No, it is perfectly legal as long as it is used on your own property.
No, only certain ways of testing them and only if a country agrees to the terms of that treaty.
Some bombs are nuclear. But most bombs are not nuclear.
yes, some people research and try to make nuclear bombs in their own houses.
Beacause millions of lives were taken by the nuclear bombs
At this time the US builds no nuclear bombs. A small number of existing bombs are refurbished as needed.
Only governments have nuclear (atomic) weapons. Their use is restricted by the threat of all out nuclear war and a number of treaties.
Yes, there is nuclear energy in nuclear bombs. It is released in a few microseconds when they are detonated.
Nuclear bombs before the 60s were referred to as atom bombs, because the term Nuclear hadn't been discover yet. Nuclear bombs today, are generally Hydrogen bombs, or fusion bombs. They are significantly more powerful, able to places about the size of Rhode Island. Atom bombs,which were mostly uranium and plutonium, lack the destructive power of Nuclear or Fusion bombs.