In the following some existential risks for mankind are compared with each other. In addition to the risks mentioned here, there may be other risks (e.g. super intelligence or medical aspects).
Climate change is directly perceptible. People can already experience effects today. It is foreseeable that living conditions will deteriorate significantly. It is possible that the available habitat will become considerably smaller in the future, even if humanity as a whole is not initially in danger. However, climate change also increases the danger of armed conflicts and thus also the nuclear war risk.
With examples of killer robots and killing drones, the effects can be made very visible, which facilitates possible protest actions. Proponents of autonomous weapons argue that it is better to let machines fight than humans. If at some point only robots fight against each other and humans are spared, this might be true. However, the effects of the development of autonomous weapons are still completely unclear. Humanity as a whole does not seem to be threatened. If a UN ban is currently not yet possible, this can still be achieved after initial negative experiences, comparable to the ban on chemical weapons.
Nuclear War Risk
The risk of a nuclear war, and in particular the risk of a nuclear war by accident, cannot simply be presented and made people aware. For 74 years mankind has been living with this threat without any further use of nuclear weapons. As with other accidents in technical systems, an accidental nuclear war will break out suddenly and unpredictably as a result of an unfortunate coincidence of events within a few minutes, threatening humanity as a whole. A retrospective insight that this was not actually intended and should have been prevented would possibly come too late. In the case of weapons such as chemical weapons or autonomous weapons, a subsequent reversal after use would still be possible, but in the case of a nuclear exchange of blows it might no longer be possible. A reduction of the nuclear war risk is therefore currently the most important and urgent problem for mankind.
Mikhail Gorbachev: “Of all the problems of international security, the nuclear danger is the most urgent today”. (Book: Was jetzt auf dem Spiel steht. Mein Aufruf für Frieden und Freiheit.. Settler-Verlag, 2019, page 40)
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