Even with GPS guidance, you'll only get within a few meters of the target. Laser designation (with Copperhead guided projectile) works well if the antomospheric conditions are possible.
What's less appreciated is that in the old days, a really good 8" (203mm) howitzer crew, with a good tube, registered, good data on the met, powder, etc., a good FDC and first order survey, could reliably put a round in a target the size of a largish door. (Specifically, an inert round put through the door to the Blockhouse on Signal Mountain for all you Redlegs who've been to the Commanche County Cannon College) - I first heard about that from a guy who was there during WWII, but I saw demonstration batteries put 8" rounds on specific car/truck body wrecks out on the range in the mid-1970s.
"What's less appreciated is that in the old days, a really good 8" (203mm) howitzer crew, with a good tube, registered, good data on the met, powder, etc., a good FDC and first order survey, could reliably put a round in a target the size of a largish door. (Specifically, an inert round put through the door to the Blockhouse on Signal Mountain for all you Redlegs who've been to the Commanche County Cannon College) - I first heard about that from a guy who was there during WWII, but I saw demonstration batteries put 8" rounds on specific car/truck body wrecks out on the range in the mid-1970s."
Amazing what they overcame when it was necessary. Of other interest in WWII was the fuses they designed for anti-aircraft to explode when it neared an enemy plane. They had to use radio waves and vacuum tubes.