Taiwan would be one area that the Chinese need to build up for. An invasion against Taiwan will require naval superiority in the area in order to move and supply the huge amount of troops, weapons, and supply; and China doesn't have that capability . . . Yet.
I feel that if China invaded Taiwan, America would become involved. The PRC refuses to have diplomatic relations with any nation that recognizes the ROC (Taiwan), and requires all nations with which it has diplomatic relations to make a statement recognizing its claims to Taiwan. This is why you see the political tap-dancing form the United states when dealing with China. Despite attempts to not provoke the Chinese by referring to Taiwan as an independent nation, and our withdrawl from the Sino-American Mutual Defense Treaty, America has agreements with Taiwan that would almost require us to intervene anyway. The Taiwan Relations Act states that the United States will "consider any effort to determine the future of Taiwan by other than peaceful means, including by boycotts or embargoes, a threat to the peace and security of the Western Pacific area and is of grave concern to the United States"
Japans concerns would be less than Taiwan regarding invasion, although a hostile naval presence in the home waters will greatly affect the Japanese economy should shipping be disrupted, and by extension, so will the United states economy. In the event of a hostile act upon Japan, the United States would certainly enter the conflict, if it wasn't already.
An invasion of Taiwan is highly unlikely given how much the two states have been moving towards some form of co-existence. And to say that China will not have diplomatic relations with nations that recognize Taiwan ROC is absurd.
Singapore recognizes Taiwan as an independent nation [Mod Edit: Text in bold technically not true. Singapore has a One-China policy and this has been reaffirmed many times. Our PM, Lee Hsien Loong has been quoted as follows: "Singapore consistently maintains a "One China" policy and opposes independence for Taiwan. We took this fundamental position even before we established diplomatic relations with the PRC."] and both the PRC and ROC have an embassy there. We send troops to train in Taiwan and China makes little fuss. China also works with other ASEAN countries that recognize Taiwan ROC.
I highly doubt the Chinese would be interested in Australia. Why go for koalas and kangaroos when they have pandas? Like these
fellows
what would the objectives be for the Chinese Navy and where can it flex its muscles
South China Sea but also some anti-piracy work off Somalia. I know they're not happy that their ships are getting boarded so last I've heard, they've been convoying them and sometimes with naval escort. Though they don't need aircraft carriers for that. But mainly South China Seas and the Pacific would be the focus since, if they are true to their word, the goal is defensive rather than offensive.
Would Taiwan be the number 1 area for some sort of aggression and would the Americans become involved considering the financial issues they have?
Unless the US wants to desert an ally, it will have to intervene. Otherwise, how could other regional allies take the US at its word when the precedent is set that "Oh, sorry, can't afford this war. can't send those troops we promised X years ago. Good luck on your own!"
What would the Japanese concerns be?
Simple, what are China's ambitions? The PRC is hardly a transparent nation and its motives are fairly unknown. Some would say that it is planning to re-assert itself as THE Asian power. Considering its history, I wouldn't be surprised if that does play a role. The 100 Years of Shame must still ring in some ears.
Then there's the fact that China and Japan have hardly had the best of relations in the past 100 years, it's not surprising the Japanese are a little concerned. And then China's rapid military growth and rather strange form of government (e.g. capitalist in practice, communist in rhetoric) makes it difficult to know what's an act, what's real and what's them trying to pull our legs. After all, thousands of years as the Middle Kingdom was interrupted by Western imperialism. This created a mentality that the Chinese brought culture to others and were therefore the most civilized race in Asia. Then the British come and start dumping opium and start a war when the Chinese refuse to allow anymore drugs into the country. So from a Chinese perspective, Europeans were invaders much as the Mongols were. Now China's free, strong and able to return to its former glory, so why not?
Considering the 2008 Olympics and the effort that went into the event, I think its safe to say that China is not looking for armed conflict with other world powers. Recall who owns a large chunk of US debt? Only to show that it will assert itself and will not be pushed around anymore. Perhaps a little rosy on my part but I don't think the US is doing much to minimize tensions either.
