It's not technically post apocalyptic but close enough.
The book takes place in the run up to the second Iraq War. It's just before the invasion when a wave of energy of indterminiate origin cuts off all of Mexico, parts of Cuba, Most of the US except for Western Washington, Alaska and Hawaii and parts of Canada. Every living thing (excluding plants) within the wave vanishes.
It's very strange to read about actual people as minor characters (mostly the generals). The Seattle City Council members are made up but Gary Locke was governor at the time. It's interesting reading about how Seattle would fare. I'm not sure if he's right or not. Although I am sure there would be lots of pointless bickering.
It was an interesting look at how the remnants of the US would cope as well as how the sudden disappearance would affect the rest of the world.
I'm really looking forward to the next book in the series.