Quite why only four of the world's nations have recognised the advantages of the Harrier to the extent of buying the hardware and placing it into service is doubtless a complex question, but to the layman it must rate as one of the major aviation mysteries of the age. It seems incredible to many that combat aircraft - the most flexible weapons of modern warfare - should be dependent for their operation on hundreds of yards of flat concrete for years targeted with pinpoint accuracy; as a corollary, since a situation could well develop wherein it is the only effective machine that survives into D+1, it also seems strange the Harrier is not filling service inventories across the globe to the point of overflowing...