tatare - I think you need to remember the distances - from the northern most point of Iran Jaya to Darwin is 1400 kms - as post 20 points out that really restricts how many RAAF fighters can go north (2) and that applies in spades to anyone coming the other way. It's easy to say " the Chinese can just sail around Indonesia" but from the N end of the Philippines to New Caledonia by sea is 6700 kms - roughly the same as from Murmansk to Boston Harbor