This was written as the third book in an initial series of three. Pedro Six Two looks at the disaster and the possible resulting societal fallout from a decidedly military viewpoint. These three books set the parameters for the entire sroty arc.
Where the First Strike story was the series set up, Going Home examined issues related to self-defense for both homes and communities, Pedro Six Two looks at different issues. Some examples would be the impact from lack of spares for high tech military systems or how the battle to secure a large city might occur. This book series takes it as a given that large gangs exist - they do right now - and that displaced people will likely become violent. That the two would work together is pure conjecture. The old saw of 'social chaos is three missed meals away' is more truth than not, one need only to look at recent history.
The book also takes a look at possible political issues, how various groups might be treated, used and abused. Finally, there is no happy ending - nor would there be in such a chaotic situation - as they say, that's real life.
The statistics for loss of life from starvation and disease the characters talk about are at the low end of the open source data I could find in my research. Once the magic stops - and delivery of food to your local grocery store ceases, the electricity is gone and so is the water, lights and refrigerator - life will be vastly different. For some people, life will be vastly shorter as well.
As you read this book series, I hope you examine your own situation and take steps to ensure you, your family, and loved ones can weather a storm of any type, natural or manmade.
Enjoy