Satellite photos show China making rapid progress in building new islands in the Spratly islands. Some of these new islands are large enough for airstrips long enough to support warplanes, but most are suitable only for light transports and helicopters. This, however, makes these new islands suitable as staging areas for helicopter raids on nearby small islands claimed, or even occupied, by another nation. In effect, these new islands have become permanent aircraft carriers dotting the disputed islands of the South China Sea.
In the last year or so China has rapidly gone from building platforms to bringing in dredging ships and piling up sand into new islands. Thus Hughes reef, which has had a 380 square meter (4,100 square feet) raised platform since 2004 has in the last six months had that expanded by dredging to a 75,000 square meter (18 acre) island with an airstrip and buildings now under construction. Similar platform building and island creation is under way at other reefs (Johnson South, Gaven Reefs and Fiery Cross Reef) in the Spratlys.
China is particularly concerned about gaining control of the Spratlys, a group of some 100 islets, atolls, and reefs that total only about 5 square kilometers (1,200 acres) of land, but sprawl across some 410,000 square kilometers of the South China Sea. Set amid some of the world's most productive fishing grounds, the islands are believed to have enormous oil and gas reserves. Several nations have overlapping claims on the group. About 45 of the islands are currently occupied by small numbers of military personnel. China claims them all, but long occupied only 8 while Vietnam has occupied or marked 25, the Philippines 8, Malaysia 6, and Taiwan one. Now China is building platforms and new islands all over the Spratly chain giving it a legal (at least according to China) claim to all of the Spratly Islands.
All these new islands have to be supplied with food, water, fuel and other necessities from the mainland. Most of this is by ship but the addition of airstrips provides the ability to make emergency deliveries by air. The platforms are kept because during major storms these low lying artificial islands are often flooded. The platforms provide an emergency refuge for the small garrisons on these islands. Other nations believe all this platform and island building can mean only one things, an eventual Chinese attack on the claims (and island garrisons) of other claimants.