Illegality of nuclear weapons

The International Court of Justice delivered on 8th July 1996 its Advisory Opinion on the Legality of the Threat or Use of Nuclear Weapons. With this Advisory Opinion the Court gave a authoritative interpretation of the relevant rules of international law.

On which rules of law did the ICJ base the Advisory Opinion?

As cardinal principles the Court mentions the following:
"The first is aimed at the protection of the civilian population and civilian objects and establishes the distinction between combatants and non-combatants; States must never make civilians the object of attack and must consequently never use weapons that are incapable of distinguishing between civilian and military targets. According to the second principle, it is prohibited to cause unnecessary suffering to combatants : it is accordingly prohibited to use weapons causing them such harm or uselessly aggravating their suffering. In application of that second principle, States do not have unlimited freedom of choice of means in the weapons they use"

With nuclear weapons it is impossible to respect these rules. Their destructive power is enormous and the consequences of the use of a nuclear weapon, like fall-out or the long-term radioactivity of the spread particles, can not be contained in time or space. Their destructive power has effects far outside the military target and more than what is in any case acceptable as 'collateral damage', which means that no distinction can be made between civilians and combattants. The radioactivity has consequences long after the actual military confrontation and thereby causes unnecessary suffering.


Is the Advisory Opinion of the ICJ binding or not?

International law itself is binding and it is international law which makes nuclear weapons illegal, not the Advisory Opinion. This is only an authorative interpretation of the law.
As such a judicial decision is only binding for the parties and only for the case which was under consideration, but it can be a authoritative on the interpretation made of the law. This is true as well for the Court of Cassation, the highest Belgian court. Ex. the interpretation made by the ICJ in the Arrest Warant- or Yerodia-case of international law was applied not only in the Yerodia case but in other cases as well.
In an Advisory Opinion-procedure before the ICJ there are no parties like in a contentious procedure. But the interpretation of the law stays a judgment concerning this law by the highest competent court and may not be ignored.

The ICJ did not come to a decision for the "extreme circumstance of self-defence, in which the very survival of a State would be at stake". Does this make the actual nuclear weapons policy legal?

The ICJ did not come to a decision, which is not the same as saying that the use of nuclear weapons would be legal in this situation. The rules of international law apply as well in these circumstances. But the ICJ had not the necessary elements of fact at its disposal to come to a definitive conclusion.
The ICJ had to make a decision on nuclear weapons in general, which is a very broad question. The president of the Court stated that the existing nuclear weapons are clearly illegal but that he could not conclude on possible technological developments in the future. To conclude for illegality also for these future developments a treaty is needed.

But when we talk about the nuclear weapons on Kleine Brogel or elsewhere it are specific nuclear weapons we are talking about. The factual knowledge is available to come to a conclusion and to conclude for the illegality. A similar approach can be taken for all the different types of nuclear weapons. This Advisory Opinion implies therefore the illegality of all existing nuclear weapons.

For an extensive analysis of international humanitarian law and nuclear weapons