80 years ago, people in the cities of Hiroshima and Nagasaki experienced the indescribable horror of an atomic bomb being dropped. Since then, the survivors of this catastrophe have been warning of the consequences of the use of nuclear weapons. In Germany, more than 600 cities are therefore raising the "Mayors for Peace" flag on July 8 to make a clear commitment to nuclear disarmament, against war and for peaceful coexistence among people worldwide.
Mayor Katja Dörner: "Nuclear weapons do not create more security, but are a risk for all of humanity. As Mayors for Peace, we are therefore committed to the abolition of nuclear weapons. Raising the flag here in Bonn and in front of the many town halls around the world is more than a symbolic act. It is a commitment to global solidarity, disarmament and the protection of peace. As the German city of the United Nations, home to many international organizations and the venue for important conferences, we in Bonn have a special responsibility and the opportunity to exert influence."
According to Mayors for Peace, the annual report by the Stockholm International Peace Research Institute (SIPRI) shows that the number of nuclear warheads has been reduced to an estimated 12,120. However, the number of warheads kept on high alert has risen to around 2,100. Nine countries have nuclear weapons, with the USA and Russia possessing most of the weapons that are acutely operational. China is rapidly expanding its nuclear arsenal. SIPRI sees efforts to modernize stockpiles in all nuclear-armed states.
Experts from the Stockholm International Peace Research Institute (SIPRI) estimate that there are currently around 12,241 nuclear warheads worldwide. Almost all nine nuclear powers are modernizing their arsenals, with China's nuclear arsenal growing particularly rapidly. In addition, the New START Treaty, which was extended for five years in 2021 and regulates the limitation of strategic nuclear weapons between the USA and Russia, expires at the beginning of next year. Efforts to extend or replace it are apparently not in sight.
The flag day
On Flag Day, Mayors for Peace recall a legal opinion issued by the International Court of Justice in The Hague on July 8, 1996, which found that the threat of use and the use of nuclear weapons generally violate international law. The Court also noted that there is an obligation under international law "to conduct and conclude negotiations in good faith leading to nuclear disarmament in all its aspects under strict and effective international control."
To mark Flag Day on 8 July 2025, the Bonn Peace Forum, which is made up of various initiatives and individuals, is organizing a rally in front of the Old Town Hall at around 12 noon on that day. Deputy Mayor Nicole Unterseh will give a welcoming address on behalf of Mayor Katja Dörner.
Bonn is a "Mayors of Peace" city and part of the ICAN Cities Appeal
The city of Bonn has been a member of the "Mayors for Peace" network since 2009. Founded in 1982 by the mayor of Hiroshima, the association is primarily committed to the abolition of nuclear weapons, but also addresses current issues in order to discuss ways of peaceful coexistence. More than 8,480 cities in 166 countries belong to the network, including around 900 cities in Germany. Bonn regularly participates in the network's flag-raising days on July 8 and September 21 (UN Peace Day). In 2025, around 600 German cities will fly the network flag. Further information on the network can be found at www.mayorsforpeace.de (opens in a new tab).
In addition, on September 16, 2021, the Bonn City Council followed a request from Bonn's peace groups and joined the ICAN (International Campaign to Abolish Nuclear Weapons) City Appeal. This calls on the German government to join the UN Treaty on the Prohibition of Nuclear Weapons.