Nuclear weapons, biological weapons, and chemical weapons (aka, weapons of mass destruction) are different from other weapons because they:
Proliferation of nuclear weapons refers to the spread of nuclear weapons amongst different countries. First the U.S. had a nuclear bomb; then the Soviet Union had a nuclear bomb, followed by other countries such as the United Kingdom, France, China, India, and so on.
NO. Afghanistan does not have nuclear weapons, nor did it have nuclear weapons at any time, nor has it been accused by other countries of having nuclear weapons. Afghanistan is also a signatory to the Nuclear Non-Proliferation Treaty, for what that's worth.
There were tests of nuclear weapons but no other nuclear weapons were dropped on other nations as an act of war. Hiroshima and Nagasaki are the only uses of atomic weapons on other nations.
Neither the US nor Russia makes new nuclear weapons. The US refurbishes existing nuclear weapons at the Pantex plant outside Amarillo, TX. Russia has a similar facility operated by a corporation called Rosatom, but I don't know where exactly. Other countries may be making small quanties of new nuclear weapons.
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I know of no "nuclear biological" weapons, perhaps you meant nuclear, biological, chemical (NBC) weapons, which can be any one of these.
Yes hence the word NUCLEAR WEAPONS
A war where countries fight each other with nuclear weapons.
They don't have any less of a right to have nuclear weapons than any other country.
To prevent the spread of nuclear weapons to other nations.
NO for Afghanistan; YES for Pakistan. Afghanistan does not have nuclear weapons, nor did it have nuclear weapons at any time, nor has it been accused by other countries of having nuclear weapons. Afghanistan is also a signatory to the Nuclear Non-Proliferation Treaty, for what that's worth.Pakistan confirmed its first nuclear weapons tests in 1998.
Countries with nuclear weapons often push for non-proliferation to prevent other nations from acquiring such weapons. While each country has sovereignty, there are international agreements like the Non-Proliferation Treaty aimed at preventing the spread of nuclear weapons. It is generally in the global interest to limit the number of countries with nuclear capabilities to maintain stability.