Charles Ellicott Commentary 2 Kings 19:11

"Behold, thou hast heard what the kings of Assyria have done to all lands, by destroying them utterly: and shalt thou be delivered?" — 2 Kings 19:11 (ASV)

All lands, by destroying them utterly. — All the countries, by putting them under the ban, i.e., solemnly devoting all that lived in them to extermination.