 Due to the diminishing threat of enemy surface attack as World War II progressed, especially on the east coast, of 38 16-inch batteries proposed only 21 were completed, and not all of these were armed.As the 16-inch batteries were completed the older heavy weapons at the harbor defense commands were scrapped, though some 6-inch and 3-inch guns were retained.Following World War II essentially all remaining gun defenses were scrapped by 1948.