As Nuclear Proliferation Treaty Turns 50, Hundreds of Warheads Remain Outside Deal's Umbrella

Today marks the 50th anniversary of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT), which came into force on March 5, 1970.

The treaty was designed to prevent nuclear proliferation, promote disarmament and encourage the peaceful use of nuclear energy for all nations. Since it became active, four new nations have developed nuclear weapons, though global atomic stockpiles have decreased significantly.

There are around 14,000 nuclear warheads worldwide, 90 percent of which belong to the U.S. (6,185) and Russia (6,500). Around 3,750 are deployed with operational forces, according to the Stockholm International Peace Research Institute.

The total number is down from a peak of around 70,300 in 1986. The NPT has been key in achieving this reduction, providing a framework for disarmament negotiations and further arms control treaties.

Névine Schepers, a non-proliferation and nuclear policy research associate at the International Institute for Strategic Studies, told Newsweek that the NPT should be celebrated for managing to contain proliferation and enable peaceful use of nuclear technology.

But a handful of nations and hundreds of nuclear weapons remain outside the NPT umbrella. India, Pakistan and Israel have not signed the treaty, while North Korea left it in 2003. In total, these countries are believed to hold some 420 warheads between them. South Sudan, founded in 2011, has also not signed, though is not part of the nuclear club.

Historic rivals India and Pakistan have both refused to sign. India was the first of the two to go nuclear, testing its first atomic device in 1974. It has since built up an arsenal of around 140 warheads.

Pakistan had been working on nuclear weapons since 1972, shortly after the country's disastrous defeat by India and what would become Bangladesh in the 1971 Indo-Pakistani War.

India's 1974 nuclear test prompted Pakistan to intensify its work on a nuclear weapon, perceiving its enemy as having achieved unacceptable military superiority. Pakistan's first nuclear tests came in 1998 as a response to a series of Indian tests. The country is now believed to have around 160 nuclear warheads.

Israel has never publicly acknowledged its nuclear weapons program, which is thought to have begun in 1958. It produced a deliverable nuclear weapon by 1966 or 1967, with full-scale development beginning after the 1967 Six-Day War.

Evidence of Israel's nuclear weapons was published by junior nuclear technician Mordechai Vanunu in 1986. Vanunu—who had been living in the U.K.—was later abducted by Mossad agents in Rome, brought back to Israel and convicted of treason.

Since then, Israel's nuclear capability has been an open secret. The country is believed to have around nuclear 90 warheads deliverable via a range of methods, including submarines, aircraft and ICBMs.

North Korea was part of the NPT but withdrew in 2003 after the U.S. stopped oil shipments to the country, accusing Pyongyang of starting an illegal enriched uranium program. The country announced it had developed a nuclear weapon in 2005, first testing a warhead the following year.

Despite a surprise detente with the U.S. and its southern neighbors, denuclearization negotiations with President Donald Trump's administration have come to naught.

North Korea has continued nuclear weapon and ballistic missile development in recent years though it has maintained a freeze on tests. Pyongyang is believed to possess around 30 warheads.

Schepers said it is "very concerning" that these nations remain outside the NPT club, though noted that without the treaty there could be dozens more nuclear-capable nations.

It is "very difficult" to discuss disarmament with non-NPT countries, she added, suggesting NPT nations must find "better ways to engage" with them without legitimizing their nuclear status.

Regardless, Schepers said the NPT has "a very great success record" and remains fit for purpose, even if its members face big questions about how to adapt to the modern world.

NPT and non-proliferation more broadly faces significant challenges in the years and decades ahead. North Korea remains outside the treaty and Iran has recently threatened to walk away following the U.S. withdrawal from the Joint Comprehensive Plan of Action. If Iran develops nuclear arms, other nations, including Saudi Arabia, will be clamoring to do the same.

Meanwhile, landmark arms control deals between the U.S. and Russia are falling apart. President George W. Bush withdrew from the Anti-Ballistic Missile Treaty and Trump ended U.S. compliance with the Intermediate-Range Nuclear Forces Treaty.

The New START agreement—the last of what former Soviet premier Mikhail Gorbachev called "three principal pillars of global strategic stability"—is set to lapse in 2021. Russia has expressed willingness to extend the deal, but the U.S. is yet to make a decision.

The Trump administration has suggested it wants to bring China into any new deal, but experts have warned this is not feasible before New START lapses.

"Most of the significant reductions that were made in nuclear warhead stockpiles over the years were thanks to these arms control agreements [between the U.S. and Russia]," Schepers said.

If New START lapses, it will mean that for the first time in 50 years "the two largest arsenals in the world are without any checks, any constraints," Schepers said.

India, ICBM, nuclear weapons, NPT, proliferation
This file photo shows an Indian Agni-5 ballistic missile during a military paraade on January 26, 2013 in New Delhi, India. Pallava Bagla/Corbis via Getty Images/Getty