The land, etc. Translate, The land shall be desolate, before whose two kings thou art afraid. The "land" must certainly be that of the two confederate kings, Rezin and Pekah, the Syro-Ephraim-itic land, or Syria and Samaria.
"Desolate" may be used physically or politically. A land is "desolate" politically when it loses the last vestige of independence.