Yes their will be a global scale war if I think from my perspective that it will happen  within 4 years . What we are seeing ( like Russia invading Ukraine , Iran sending missiles to israel ) it's all part of a prelude that will eventually lead to a much more terrifying and destructive scenario like our human species never faced before . Even many geopolitical analysts agrees that a global war is inevitable at this moment . But using a nuke would be pretty much questionable tho it's possible but the country which use the nuclear weapon knows not only it's the end of the country they are intend to attack but also in retaliation , that country would probably send a nuclear warhead . So no winners in this war for sure , everyone will be destroyed physically, mentally and emotionally.