With over 16,000 nuclear warheads in the world, humanitarian and civil-society groups are trying to sound the alarm over what a detonation - accidental or deliberate - of one of these weapons might mean.

"There is no possible winner with nuclear weapons," says Alexander Kmentt, director of the Disarmament, Arms Control and Non-Proliferation at Austria's Federal Ministry in Vienna, Austria.

"If you look at the consequences, they are far more severe than we understood before, the risks that something could go wrong are far more significant than we were lead to believe because now lots of information is becoming declassified from the Cold War era.

"There are no humanitarian counterarguments to these points."

Indeed, from humanitarian groups, there is nothing but support for disarmament, with the International Committee of the Red Cross pointing out that a nuclear attack is something "it cannot prepare for".

Incredibly difficult task

Kmentt is part of an effort pushing for nuclear disarmament, which while a stated goal within the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) - is an incredibly difficult task.

"Maybe humans are not actually capable of conceiving of such a total catastrophic outcome - of a real civilisation-ending scenario," said Kmentt, adding that prevention of a detonation is the only way, because "there will not be an opportunity to learn from our mistakes".

In addition to levelling cities leading to a massive number of deaths and injuries, an detonated nuclear warhead could result in radioactive contamination, illnesses and, yes, a nuclear winter, damaging crops, triggering a massive food security nightmare.

[You can go to NUKEMAP, enter a location and weapon to see what kind of fallout and casualty an explosion there would result from a given detonation.]

Rights groups linked up with nongovernmental organisations [such as The Vienna Centre for Disarmament and Non-Proliferation], as well as states that are keen to rid the world of nuclear weapons at a perceptible pace, are trying to move things forward, but states with nuclear weapons are slow to come around.

At the second international conference on the humanitarian consequences of nuclear weapons, not a single one of the nuclear weapon states recognised by the NPT showed up in February.

This time around, the US and the UK are coming to the table, something Kmentt, using the language of diplomacy, attributes to "discussions" and "efforts" in the in intervening months before the previous conference in Nayarit, Mexico, and the upcoming one on December 8 and 9 at the Vienna Conference on the Humanitarian Impact of Nuclear Weapons.

'You go first' principle

This is a start, but in the world of nuclear disarmament, the name of the game is "You go first" - no one wants to rid themselves of their weapons first, and point to the step-by-step process of gradual disarmament that the P5 have agreed upon

"I would say that none of these initiatives would take place if this step-by-step process was credible," said Kmentt.

He points out that the first step is supposed to be the CTBT [Comprehensive Test-Ban Treaty], but the treaty has not entered into force.

The second step is supposed to be the Fissile Material Cutoff Treaty, negotiations for that treaty have not yet begun.

"So the credibility of the implementation of the disarmament obligation is not really there," he said.

The argument for having nuclear weapons essentially comes down to security, something Kmentt dismisses.

"By insisting on having nuclear weapons for their own security, states that have them permanently proliferate the concept of nuclear weapons," he said.

"How can we ensure proliferation doesn’t happen if those that have it [nuclear weapons] equate it with powerful status and with the necessity for their own security?"

Forget about a detonation caused by "conflict escalation", the number of near-misses one finds scattered in reports here and there is alarming.

Factoring in probability

For example, an April 14 Chatham House report outlined the risks - factoring in probability and consequence highlights several near-misses that have to do with mistakes, espionage, and technical errors, such as the incident in August 2007, when a US Air Force B-52 bomber was "flown from Minot Air Force Base to Barksdale Air Force Base, apparently without the pilot and crew being aware of the fact that it was armed with six nuclear-tipped cruise missiles".

And that's only in the case of an accident. In the case of deliberate attack, things would be no better - there's no such things as targeted or limited strike, which seems possible as the shadows of a new Cold War between Russia and the West emerge.

"The words that we use in this nuclear weapons world are bizarre, because 'limited nuclear exchange' in itself is nonsense ... Africa is a big nuclear-weapon-free zone. They've done everything necessary for their own continent to not be affected by nuclear weapons, yet they would suffer the consequences from a conflict which they have absolutely nothing do with," said Kmentt, pointing out to the crops that would be destroyed in the climate change triggered by the explosion.

International Humanitarian Law, which is aimed at protecting those who are not participating in an armed conflict and seeks to restrict "the means and methods of warfare".

Violations of these laws - which include elements of international criminal, human rights and refugee laws - are deemed war crimes. Witnessing this on a nuclear scale is something Kmentt hopes to avoid.

"It took Copernicus some time to convince everyone that in fact it was the Earth that went around the sun and not the other way around, and we hope to have a moment where we change the paradigm," he said.

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