While the chance of the scenario is hopefully slim, I think folks are looking at it backwards. He is not talking about just enacting martial law as a power ploy, but in the event of a currency event. Currency events do happen and anyone who has payed attention to the exponential growth in the US debt, coupled with the droughts causing food supply wrinkles, may see how it is a possibility. That does not mean it will happen.
In the event that there is a collapse, they will have to enact martial law. There will be no choice because people will go ape #### without their cokes, big macs and tv. They will block off major cities and corral people and distribute food. It will be a humanitarian effort or at least appear that way.
While it does appear unlikely, especially given our historical context and perception, most everything in the article has some legitimacy with the exception perhaps of the coordinated preparing between the military and the local law enforcement, since I'd like to think one of our friends here may would leak that sort of info.
Then again, maybe he just owns stock in mountain house.