So if a grunt puts on a Class IV vest with ceramic chest and back plates, he's reasonably protected from AK-47 fire. If he gets hit directly with an RPG round, he's toast.If said grunt jumps into an M113, Stryker, or LAV III, he's reasonably protected from AK-47 fire. If the vehicle gets hit directly with an RPG round, he's toast.
So what's the point?! Why not just have cheap, high-speed vehicles if your "heavy" armor can't defend against an RPG or mortar round?
Or better yet, why not field vehicles that are designed to patrol in areas saturated with RPG and mortar-armed enemies (i.e. to shrug off hits from said weapons)? Why have wheels instead of tracks if the wheels simply equate to being immobilized in mud?
But this in between stage, where the armor weighs a lot yet still doesn't protect against RPG's seems like a poor trade-off as you get neither speed nor additional defensive protection. Paying $millions$ for vehicles that are being taken out with $35 RPG and mortar rounds just doesn't make sense.
So with that said, it's a good thing that the Jihadis are poorly trained, generally ignorant, incoherent fighting forces against us.
We're seeing firsthand which equipment works, and which were ill-thought-out compromises. We'll become a better fighting force for these lessons paid in our blood (which thankfully isn't being made worse by a more skilled foe at the moment).