Albert Barnes Commentary Lamentations 4:12

"The kings of the earth believed not, neither all the inhabitants of the world, That the adversary and the enemy would enter into the gates of Jerusalem." — Lamentations 4:12 (ASV)

Though Jerusalem had been several times captured (1 Kings 14:26; 2 Kings 14:13; 2 Kings 23:33–35), yet it had been so strongly fortified by Uzziah and his successors as to have been made virtually impregnable. Its present capture by Nebuchadnezzar had cost him a year and a half’s siege.