Fewer but deadlier nukes

There are fewer and fewer nuclear weapons around the world, thanks to the New START disarmament treaty between the US and Russia, according to the newest report of the Stockholm International Peace Research Institute (SIPRI).

But even when the two top nuclear powers reduce the number of warheads according to the treaty, it wouldn't necessarily be a proof for real disarmament.

"A lot of the warheads that are being reduced or eliminated are actually aging or obsolete. They are the legacy of the Cold War," said Shannon Kile, one of the lead authors of the SIPRI report.

"In terms of operational forces the actual reductions have been quite modest."

Unfulfilled hopes

No one believed New START (Strategic Arms Reduction Treaty), which came into effect between Russia and the US in 2011, would turn the world into a nuclear-free zone in the foreseeable future.

"That is disappointing," said Annette Schaper, project manager and expert for nuclear disarmament at the Peace Research Institute in Frankfurt.

That is mainly because of the difficult relation between Russia and the US, she said. "Russia should have been more involved and should have been taken more seriously in the NATO-Russia Council than is now the case."

Schaper is also disappointed that nuclear weapons are still stationed in Germany. She called this an "anachronism."

"They should have been disarmed and removed. But NATO is not yet ready for it."

Nuclear dwarfs and nuclear giants

Russia and the US possess the overwhelming majority of the world's nuclear weapons - more than 90 percent of them. But the report said smaller nuclear powers also appear to be following the trend of modernization.

France and Britain are already either modernizing their nuclear weapons or are planning to do so, Kile said, suggesting they have no intention to give up their nuclear weapons in the foreseeable future, he said.

"China appears to have embarked upon a long-term modernization program, but the focus is more on quality improvement to its forces rather than quantitative improvements," Kile said.

India and Pakistan are also upgrading their weapon arsenals

Two smaller nuclear powers are worrying him more: "India and Pakistan are both known that they are expanding the size and sophistication of their nuclear arsenal," he said, adding that this was especially alarming because their weapons could now be deployed faster and be used against conventional armed forces, increasing the risk of conflict.

The arms race has developed its own dynamic in these two countries, Schaper said. "Pakistan feels threatened by India. The Indians are looking more at China."

North Korea - the great unknown

North Korea, the smallest nuclear power, is a special case. "It is a complete outsider that can only stabilize internal threats through an alleged external threat," said Schaper.

But it is obvious that the isolated country is qualitatively improving its nuclear weapons. Previously experts assumed that North Korea had "primitive nuclear devices," she said. Today, most believe North Korea possesses functional nuclear weapons.

Israel's secret nuclear weapons

Israel also possesses nuclear weapons, Kile said. The country has never officially admitted that is has nuclear weapons, but they are an "open secret." The extent of the Israeli nuclear program seems to be stable, but this could change.

"Israel seems to be in a wait-and- see mode regarding what happens in Iran. And if Iran would develop a nuclear weapon we might see a change in the Israeli arsenal," he said.

In recent years, many nuclear weapons have been destroyed due to the disarmament agreements between Russia and the US, Kile said. At the peak of the Cold War, there were nearly 60,000 nuclear warheads on both sides. Today that number is down to around 16,000, but "16,000 nuclear weapons in the world is still an extraordinary high number."