[GCU-Empiricist]

SO the US military is heavily reliant on GPS, and they know it, and so do professionals on the other side. There is a lot of good reason to think that if the US gets into a Large State action, which is relatively unlikely but. . . , then the opposition will employ GPS jamming to negate some of the more smart and collateral damage avoiding systems. I've been out for almost a decade, so I don't know if secondary powers have reliable and ubiquitous GPS jamming capabilities, but I'd bet dollars to donuts IRAN has spent significant funding to acquire GPS jamming. All of this gives a a context for why the military both uses training aids (marker blackout over GPS, manually disabled data links, and whatever more high tech the have devised) and real operate in jamming training, possibly as final training, certification training/exams, if my experience in sibling forces is any guide.