The drums of war are beating. North Korea has sent a second missile, without Japan's consent, over the top of Japanese territory. This comes only a few days after they exploded a nuclear device which was over 10 times larger than what destroyed Hiroshima in 1945. They then threatened their neighbour, "the four islands of the archipelago should be sunken into the sea by the nuclear bomb of Juche. Japan is no longer needed to exist near us".

In this extreme climate, rather than walk away and believe that war is inevitable, the international community must remain calm, speak with one voice and continue to ratchet up the sanctions on North Korea. Sanctions are designed to cause pain to a country in an attempt to make them change their direction. They can start off very soft, covering a small list of luxury items and then escalate to being very hard, covering every aspect of a country's existence. Although the pain caused by sanctions is regrettable, they are always preferable to war and this option must always be fully explored before considerations of violence are raised. Violence can never be anything but the last resort. If war breaks out on the Korean Peninsula there will be no winners, only degrees of loss between extreme and cataclysmic.

The Charter of the United Nations gives the Security Council the right to insist that all countries apply the sanctions they deem necessary to bend a country to the will of the international community. Such efforts represent the collective will of the global community to pressure, without violence, dangerous or highly disagreeable countries. Although such sanctions should not cover medicine or food, everything else is on the table.

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The UN first applied sanctions on North Korea for their nuclear and missile programme in 2006. Since that point, with every significant breach of the demands of the Security Council, the sanctions have been increased. We are now at the point where the sanctions have reached a height which is near unprecedented compared with those applied to other countries over the last seven decades.

While Vladimir Putin was probably correct when he said that North Korea's Kim Jong-un would rather have his people "eat grass" before giving up his nuclear weapons and ballistic missile programme, the reality is that if recourse to war is to be avoided, the option of further sanctions applying maximum pressure on North Korea must first be exhausted.

Although unprecedented, there is still room to increase the sanctions even further. First, the current cap put on North Korean workers outside of their country could be reduced to zero. Second, a complete travel ban covering all North Korean citizens, including students and sports teams, right to the top of its leadership could be implemented. Third, all diplomatic relations could be severed with all of the foreign embassies in Pyongyang closed, and matched by the declaring of all North Korean diplomatic staff abroad persona non-grata. Fourth, the current cap on oil imports could be reduced to zero. Reducing oil to belligerent and aggressive nations is always very provocative as few measures can do more to disrupt modern military forces than removing their fuel source. Tanks and planes find it very hard to move when powered by coal.

The problem with all of these additional options is that for sanctions to work the leadership of the targeted country must be susceptible to the pain the measures cause. Sanctions worked on Iran because it wanted to be connected to the international economy, it was cosmopolitan in outlook, and its leaders could hear the discontent that the sanctions were causing on their population.

This is not the case in North Korea. This regime is deaf to their population and naturally isolationist in character. From the famines in the 1990s through to the human rights abuses in the 21st century, the Kim family dynasty has no counterparts in terms of repression. A 2014 UN Commission of Inquiry found that the gravity, scale and nature of their systematic, widespread and gross human rights violations and crimes against humanity do not have parallel in the contemporary world. Their crimes include extermination, murder, enslavement, rape, forced abortion and other sexual violence. Secretive prison camps hold opponents and/or critics, in which torture, starvation rations and forced labour are common. In North Korea, there is no freedom of speech, freedom of the press, freedom of religion, free trade unions or any independent civil society. Even freedom of movement to other countries is increasingly rare. Political opposition is prohibited. Arbitrary arrest, collective punishments and public executions maintain an environment of fear and control.

The problem that the international community now faces is that this North Korean regime which is impervious to pain, is the very one that it is trying to bend to its will with sanctions. While Vladimir Putin was probably correct when he said that North Korea's Kim Jong-un would rather have his people "eat grass" before giving up his nuclear weapons and ballistic missile programme, the reality is that if recourse to war is to be avoided, the option of further sanctions applying maximum pressure on North Korea must first be exhausted. War is not inevitable.

Alexander Gillespie is professor of international law at the University of Waikato, New Zealand. His research focuses on laws of war and armed conflict. He is the author of the three-volume set "A History of the Laws of War" and the three-volume set "The Causes of War".

The views expressed in this article are the author's own and do not necessarily reflect Al Jazeera's editorial policy.