I find it funny that one of the best solutions to killing a sniper is to direct an entire artillery barrage near his last known position.
Oh well, if the US army right now calls in AC-130, Apache, F-15, F-16, A-10, Predator, Reaper support versus any group of fighters shooting a gun in the general direction of US troops then it isn't too far off for WW2 howitzers to target snipers