Answer 1
This is mainly due to the technology. Some countries who are in possession of technology and raw material , because of political reasons maintaining their supremacy moral policing type towards those which do not have. Also they wanted to create a sense of fear among them for themselves.
Answer 2
The Nuclear Non-Proliferation Treaty sets out that only the US, UK, France, Russia, and China are allowed to have nuclear weapons, since the treaty was written at a point when all five were nuclear powers already. Most countries signed the treaty and so the requirement to not have nuclear weapons was binding on them. India, Pakistan, and Israel did not sign the treaty, so the restriction was never binding on them. North Korea has nuclear weapons illegally and has been sanctioned on that account.
Pakistan has about 100 nuclear weapons.
The first Islamic country to have nuclear weapons was Pakistan.
India and Pakistan
Today eight countries are in possessionn of nuclear weapons. The five nuclear weapons states United States, Russia (former Soviet Union), United Kingdom, France and China, are the only countries allowed to have nuclear weapons according to the Non-Proliferation Treaty (NPT) from 1970. All members of the United Nations except Israel, India and Pakistan have signed the NPT.
India and Pakistan
Pakistan is the only Muslim-majority country to possess nuclear weapons.
Australia and new zealand
This question is based on an incorrect underlying assumption, namely that Nixon had anything to do with Pakistan's nuclear arsenal. Pakistan acquired Nuclear technology in 1999-2000. Nixon died in 1994 and resigned from the Presidency in 1974. There is no way he could have allowed them to gain nuclear weapons.
USA, UK, France, Russia, China, India and Pakistan
India & Pakistan
u.s.;china;russia;great britain;france;india;pakistan;israel
US, UK, Russia, France, China, India, Israel, Pakistan, North Korea, South Africa are the countries that currently have nuclear weapons.