Reddit, how would World war III play out if it were to happen today? Let's have a virtual war-game!

After reading the insightful and well researched comments from this post and gaining inspiration from this wikipedia article, I was wondering how Reddit thinks a third world war would go. What would initiate it? Who would join in? Where will the battles take place? Who would rise up as leaders?

We can use information publically available on the internet to plan out potential scenarios and use history to predict their most likely outcome!

Here is a List of Countries by Level of Military Equipment and a List of Countries by Number of Troops to get you started.

So how do we do this?

Well there are many potential starting points/acts of war that could trigger this. The main reply threads would pick one possible scenario. The replies to that comment would describe a number of possible actions from different countries (Please limit it to one collection of actions per reply and just post alternate course of actions as a separate reply). Then others can join in and reply to possible reactions to those actions and so on and so forth.

I learned a lot about random bits of political and world history reading those other threads. Lets do this in the same spirit and consider what could realistically happen and then argue about their consequences rather than arguing over ideologies.