Pakistan's nuclear arsenal is currently the largest outside the five nuclear powers recognised by the NPT and will probably overtake Britain by the end of this decade.
Pakistan began its nuclear programme after the Indian nuclear test of 1974 and this accelerated when the Soviets invaded Afghanistan in 1979. Its not known when exactly Pakistan became a nuclear power, however the period from 1979-1983 is a good bet. Certainly after the mid eighties all parties concerned treated Pakistan as a defacto nuclear power. In 1998, in response to the Indian nuclear tests, Pakistan tested on its own and became a declared nuclear power.
Pakistani Delivery systems
- Ballistic Missiles
- Pakistan has a variety of land based missiles, with both liquid fuel and solid fuelled systems. All Pakistani missiles carry two designations, the first one is ' Hataf <Number>' which is what the military refers to it and a second designation which is what the manufacturer uses. Hataf means spear in Persian.
- Shaheen:. Literally "Falcon". Shaheen is a series of missiles with solid rocket motors.
- Shaheen I: A 700Km range single warhead missile
- Shaheen 1-A,. Modified version of the above. Range is classified, but estimated in the 1500-2500 km range. Features a new warhead able to better destroy protected targets and avoid Anti Ballistic Missile
- Shaheen II. A long range, 2 stage missile. Range is estimated between 2500- 4500 km. It can carry MIRV (3 of them) and it contain manoeuvrable re-entry vehicles, meaning the the RV's are able to change their trajectory in the terminal phase , fine tuning accuracy and incidentally making an Anti Missile System worse than useless. Its is  in India as it can is mobile and can be launched in minutes. It has made all strategic targets in India vulnerable, from cities and strategic weapon sites, to the heavily hardened bunkers which will protect the Indian leadership in time of war.
- Ghauri: A liquid fueled missiles system with a range between 1500-2500 km. Now considered obsolete, Derived from the Scud system, which in itself was based upon the V-2. So it is in essence the ultimate V-2.
- Short Range Missiles: A very wide variety of them. From the Nasr, with a range of 60 km all the way to the Ghaznavi, with a range of 400 km.
- Cruise Missiles
- Babur: An air and sea launched missile.Range from 700 to 1500 km. Interestingly it is based upon the US Tomahawk when some Tomahawks fell in Pakistan after the US attacks on Afghanistan in 1998.
- Ra'ad: Meaning Thunder: 500 km range air launched cruise missile.
- JF-17. A Pakistani designed multi role aircraft with a range of about 3000 km. Can probably carry Ra'ad CM making it a potent platform
- F-16: US made aircraft, although it is controversial whether they have been modified to carry such warheads (Note) While the aircraft sold to Pakistan is not designed to carry nuclear payloads, it can be modified to do so.
- ROSE Mirage: Pakistani up gradation of the French Mirage aircraft, about equivalent in capability to a mid to late model F-16. ROSE? Retrofit of Strike Element (http://en.wikipedia.org/wiki/Project_ROSE).
PAK, in persian means "Pure" and PAK is also the first syllabal of Pakistan and a often used (in country) as a short form of the name. So Pak Attack; Pure attack, referring to the ultimate offensive nature of nuclear weapons.