Babylon, as the instrument used by God for his judicial purposes, is likened to a wine cup, which "made all the earth drunken" (comp. Jeremiah 25:15, Jeremiah 25:16); and, more than this, to a golden cup, such was the impression made upon the Jewish prophets, by Babylon's unexampled splendour.
So, in Nebuchadnezzar's vision of the image, the head of the image is of gold (Daniel 2:32, Daniel 2:38). But neither her splendour nor her honourable position as God's minister could save her from merited destruction.