The scale of the destruction made it nearly impossible for the International Committee of the Red Cross and the Japanese Red Cross Society to provide aid in the aftermath of those bombs, and the International Red Cross and Red Crescent Movement has made it clear in the decades since that “any nuclear blast would cause insurmountable challenges for humanitarian assistance”. In addition, the catastrophic consequences wrought by the use of two nuclear weapons at the end of World War II demonstrated that such weapons are both disproportionate and indiscriminate and therefore highly unlikely to meet the basic principles of international humanitarian law (IHL). IHL is the set of international laws that dictate what can and cannot be done during an armed conflict. Those laws protect people who are not or who are no longer participating in hostilities and limit the means and methods of warfare.
The existential threat posed by nuclear weapons and the impossibility of mounting a humanitarian response to their use have been the driving force behind the international campaign to ban such weapons. Thanks to incredible efforts by grassroots organisations and networks such as the International Campaign to Abolish Nuclear Weapons and the International Red Cross and Red Crescent Movement, the Treaty on the Prohibition of Nuclear Weapons (TPNW) was adopted in July 2017. The TPNW comprehensively prohibits any kind of development, possession, stationing, testing, transfer, use or threat of use, of nuclear weapons.
At present, 44 states are party to the treaty and another 41 states have signed it; signalling their intention to ratify it. The treaty will come into force 90 days after the 50th ratification.
International security arrangements are not set in stone, and can be renegotiated and modified given sufficient political will, legal expertise and diplomatic acumen. Nuclear security arrangements can give way to conventional alliances.