Politics. Where is this talk of WW3 coming from.

I’ve been on Reserve duty at Ft Bragg, NC, thinking about Japan’s attack on Pearl Harbor, my brothers and sisters in arms who perished, and how that day of infamy catapulted us into a world war which… (1/3) pic.twitter.com/C17j1VB2rL

— Tulsi Gabbard 🌺 (@TulsiGabbard) December 8, 2021

If it was just one former politician this wouldn't have hit my radar. However I monitor "prepper" websites/videos and several of them have been talking about WW3 too. Where did this come from?