Charles Ellicott Commentary Isaiah 20:6

"And the inhabitant of this coast-land shall say in that day, Behold, such is our expectation, whither we fled for help to be delivered from the king of Assyria: and we, how shall we escape?" — Isaiah 20:6 (ASV)

The inhabitant of this isle ... — Better, as elsewhere, coast-land. Here it probably refers to the whole coast of Philistia, which had been foremost in the revolt, and Phoenicia, Tyre also having joined in it (Annals of Sargon in Lenormant’s Anc. Hist., i. 396). Cyprus, the conquest of which Sargon records (Records of the Past, vii. 51), may also be included. The whole sea-board population would find out too late that they could not resist Assyria even with the help of Egypt and Ethiopia.