Maybe, maybe not. There is always the potential. I think the chances are slim but the risk is high -- even with very low probability the potential consequences are enormous resulting in a significant risk. With the risk of a world war the greatest risk comes the risk of nuclear war. Especially over the past two years I have grown more wary about the risk of war between so called superpowers and the risk of nuclear war in particular. Humanity needs to learn to transcend violent conflict if we are to progress. We need to work towards the elimination of nuclear weapons globally, although there isn't a lot we can do at the individual level on that. Fortunately since WWII the world has become less violent overall and things have generally improved in a positive direction.

I disagree that everything seems pointless. If anything there is much more at stake and actions are even more important.

Lately I have been reading papers from ALLFED[1-2]. They have found quite a few alternative ways we could produce food during a sun blocking crisis and they would be enough to feed more than 8 billion people if needed through a severe nuclear winter, even if we lost all of our current agriculture. But they have also found that only few would survive if we only try to survive on stored food.

Another excellent resource for planning for the initial few moments/weeks of a nuclear war has been [3] which provides practical instructions for rapid construction of expedient fallout shelters.

Understanding these I at least have a feasible and actionable plan, and better understanding of what would be involved if worst case scenarios were to happen. It is a lot less hopeless than most believe, although still terrible.

I suggest reading through these and you can find things you can do at the individual level. Also consider supporting ALLFED as their work has potential to be highly impactful if such a scenario is ever realized.

[1] https://allfed.info [2] https://80000hours.org/podcast/episodes/david-denkenberger-s... [3] https://www.oism.org/nwss/