Ahmed Rashid in the Financial Times:
When Prime Minister Nawaz Sharif meets President Barack Obama at the White House on Wednesday, their meeting will be critical for the future course of US-Pakistan relations. One issue at the top of the agenda – alongside the future of Afghanistan, Pakistan’s own much-weakened state and attacks by terrorist groups – will be the country’s nuclear weapons programme. Pakistan’s rapid development of battlefield nuclear weapons raises many questions in the region and abroad.
Western analysts estimate Pakistan has between 100 and 120 nuclear weapons, far more than its rival India, which is believed to have 90-100. Pakistan has multiple delivery capability, such as long and short-range rockets and aircraft. It will soon add naval capability with sea-launched missiles.
Less well-known is that Pakistan has one of the fastest growing battlefield or tactical nuclear weapons programmes in the world today, according to senior western officials I have spoken with. The Americans developed the capacity to put miniaturised nuclear bombs on short-range rockets, artillery and tank shells in the 1950s – something Pakistan is apparently doing now and very successfully.
More here.