What type of event would be capable of shocking the entire world into a state of peace?

A UFO landing? A new star in the sky? A cure for death?

Perhaps a good event wouldn’t be enough. Would we need a cataclysmic event like a super volcano, sea levels rising, or a pole shift?

Could there even be an event so magnificent that it could promote every human being to turn their back on all violence and live a life of peace?