China has organized its military build up over the last decade with one apparent purpose; taking Taiwan by force. In order to do this, China must be able to control the air over the 300 kilometers of waters that separate Taiwan from the mainland. China has spent billions to buy modern Su-27s and Su-30 fighters from Russia. Modern destroyers and submarines have been bought from Russia as well, in addition to technology for AWACs type aircraft. Money has been spent to allow Chinese pilots to fly as often as their Taiwanese counterparts. China has improved it's amphibious and airborne forces and held more amphibious exercises. A major obstacle to taking Taiwan is the U.S. Navy. To deal with that, China recently launched its first modern SSBN (nuclear submarine carrying ballistic missile.) This boat can carry 16 missiles capable of reaching any target in the United States. The Chinese submarine will almost certainly be tracked by American subs, raising the risk of the Chinese SSBN being torpedoed by a U.S. attack submarine if the Chinese try and use their SSBN missiles to threaten America over support for Taiwan. The Chinese are betting that they can get lucky and evade the American SSN (nuclear attack submarine) that shadows hostile SSBNs, and make an effective threat against the United States. But even if China gets America to back off via nuclear blackmail, it's still a toss-up as to whether the Chinese can put together a military force that can overwhelm Taiwanese defenses. Launching an amphibious operation across 300 kilometers of open ocean is a formidable undertaking. There are many modern weapons, like cruise missiles and "smart" naval mines, that can make life very difficult for an amphibious force. Then again, China may just be spending all the money to make an elaborate, convincing and expensive bluff. Making Taiwan an offer they can't refuse, but that China cannot back up.