Because I live in the I-15 Idaho/Utah corridor, this entry by John Bytheway in his book, Isaiah For AirHeads (2006) is interesting on Isaiah 20:28-32:

Elder Gerald N. Lund described the enemy that covenant Israel in the kingdom of Judah faced at this time:  “The Assyrians are renowned for their brutality in warfare.  They tortured their captives.  Their armies were seemingly invincible!”  Elder Lund suggested that we imagine ourselves as covenant Israel, hiding not in Jerusalem, but on Temple Square in Salt Lake City (geography with which we are more familiar).  Then Elder Lund described the volume of territory already conquered by Assyria:

North and South Dakota are gone, Montana is gone, Wyoming is gone, Idaho is gone, and Washington and Oregon are gone, Nevada’s gone, Colorado is gone, all gone to the Assyrians, and northern Utah is gone.  And then the Lord says, “Be not afraid of the Assyrians.”  Even when you see them reach Clearfield, and Clearfield falls, don’t lose heart.  And when Syracuse and Layton and Kaysville and Fruit Heights fall?  No, don’t lose heart yet.  Do you know where Nob is?  Nob is the hill just north and west of Jerusalem that gives a military overlook of the city.  And the Assyrians reached Nob.  If we were to continue that analogy, it is like the Lord saying, “Yes, even if Woods Cross and Bountiful go down, even North Salt Lake, even if they camp on Capitol Hill, don’t lose your faith.  Why?  Because I have a scourge reserved for them.  Here is the most brutal, massive army in the history of the world to that point, camped within eyesight of Jerusalem. (“Making the Scriptures Live:  Levels of Effective Scripture Teaching” audiocassette, Side A)