It sounds to me like freeway speed + military-design tires + 100 degree weather caused the tire to overheat.
That was my initial suspicion but there was about 1/2" hole in the tread and a 2" tear in the sidewall when I first pulled up. Tire was warmer than the other 3 but going flat with 19,000 # truck rubbing you into the road will do that.
But we have been having some discussions around what tires to eventually run on our trucks. We may go with the bigger military tires with a higher speed rating (I was sitting on the speed rating for these tires when this happened) or run 2 different sets with something like super singles for mostly road type trips and keep the military tires for Baja etc. Given the cost in $ and risk of making a mistake means a lot more thought will have to go into it.
One great thing to come out of this is the way those truck handled when the blowout occurred. With any other type of single tire and an immediate deflation like we suffered it would of been a lot harder to control. It wasn't a really puckering experience considering the road had steep drop offs on either side with minimum shoulder and a lot of traffic (only 1 lane each way). Then I was able to limp along for miles on the tire to get to a much safer place. (still didn't make it to a cell service area).