Most did their own independent development.
Many countries have nuclear weapons today including the United States. China, North Korea, South Korea, and Japan also have nuclear weapons.
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the first five countries that were involved in nuclear weapons are as follows;United StatesGermanyGreat BritainRussiaArgentina
The United States does not give or sell nuclear weapons to any country. The United States has stationed nuclear weapons on the territory of many countries, but always retained full control of them.
America has the most nuclear weapons
As the category for this question is "Nuclear weapons", I'm presuming it refers to nuclear arms.As of 2012, the three countries with the largest stockpiles of nuclear weapons are, in order from most to least:RussiaUnited StatesFrance
Pakistan has about 100 nuclear weapons.
Most did their own independent development.
Very difficult to answer - since most countries are extremely secretive about the amount of nuclear weapons they have stockpiled.
No one. Most countries do not export nuclear weapons. Instead, the countries obtain (1) nuclear technology and (2) radioactive material and build it themselves.
Most countries have zero nuclear weapons.
Many countries have nuclear weapons today including the United States. China, North Korea, South Korea, and Japan also have nuclear weapons.
Some of the countries have nuclear weapons because they use them as a defense mechanism. The nuclear weapons are intended to be used whenever there is a war.
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the first five countries that were involved in nuclear weapons are as follows;United StatesGermanyGreat BritainRussiaArgentina
I believe the answer you are looking for is Japan - they had a secret nuclear weapons project which was exposed.