Islands with airfields can be very useful during wartime. That can be seen off Libya, where in the last three weeks, six French jet fighters have made emergency landings on Malta because they had mechanical problems, or were short of fuel. The island is 600 kilometers from where the fighters are dropping bombs in Libya. The French aircraft make a 2200-2500 kilometer round-trip from their airbase in Corsica to targets in Libya. There are aerial refueling aircraft available, to enable the fighters to spend more time over the target areas, but there are sometimes problems that prevent some warplanes from getting serviced.
One pair of fighters landed at Malta because one of the aircraft had mechanical problems. The other four were short of fuel. Two of the aircraft encountered an aerial tanker with equipment problems, and the other two were unable to get to a tanker in time.
Thus even in the age of aerial refueling, it's always a good idea to have an emergency landing strip. The classic example of this was the early 1945 decision to take the Japanese held island of Iwo Jima, for use as an emergency landing base for fighters and bombers attacking the Japanese home islands just to the north. Iwo Jima was invaded in February, and Japanese resistance ceased a month later. Nearly 7,000 American troops were killed while taking the island. But for the remaining five months of World War II, air strips on Iwo Jima took care of 2,400 emergency landings of fighters and heavy bombers, saving the lives of some 20,000 aircrew. Another example during World War II was Malta itself, which served as an unsinkable aircraft carrier for British forces, and withstood years of attacks by German and Italian aircraft.