About the no-fly zone or blockade, these things can only be achieved AFTER air and sea supremacy is achieved. So don't assume China can be blocked when its navy and air force are in its full strength.
Also, China has been self-reliant for the most part of its history, thanks to its large size and different terrain and various kinds of resources. Like the US without trading with China, China will suffer from a potential blockade, but it won't die. It can manufacture anything and everything you can think of in the world, as it IS the manufacturing center in the world. So China won't need to import anything. China survived without trading with anyone else for almost 500 years. The latest isolation was from 50's to early 80's. China suffered tremendously, but it survived. Of course, there is oil. Also like the US, which has oil on its own soil but decides not to extract, China also has oil deposit in Tibet/Xinjiang and Northeast. This is why China wants to hold on to Tibet and Xinjiang that much. It is true that the oil deposit in these areas is not that much and cannot be compared to what the Mid East has, but no blockade can last more than a few years. China definitely has enough to last that long.
Again, the same strategies used against small nations are useless or less effective against a large country like China, the US or Russia. A good example is WWII, Nazi Germany had no problem finishing off smaller countries. however, once they started fighting the Soviets, they could not defeat them even though they were winning battles after battles and destroying Soviet armies at the beginning. Against the Soviets, the Nazis enjoyed the same military superiority that they enjoyed in other parts of the world, but still could not win. Some might say it's the infamous Russian winter that ultimately defeated the Germans. Well, that's what happens when you fight a large nation. They typically have many different terrains and weathers and each of them needs to be dealt with using different strategy. If you slip on one of them, you will be defeated.
A small nation has less ability to absorb the blow, while a large nation can absorb the blow and at the same time absorb the resources of attackers and simply out-last their attackers.
Also, winning a war is much more than the technology. You simply cannot predict that a force can win a war because it has advanced technology. Yes, technology is absolutely important, but it's not everything. Korean War and Vietnam War are two good examples of a more technologically advanced force cannot win a war against an inferior enemy. The reason for this can be complicated, but each time the opponent came up with strategies to counter the technology. In these cases, the gap between the US and its opponent is so much wider than the current gap between the US and China. And this gap will become even smaller in the future. As the technological gap gets smaller, the technology becomes less of a factor while strategies, tactics, politics and social factors become more influential.
Also, I've noted a trend with how some posters claim how the US offense can penetrate China's defense and how China's offense won't even scratch the US' defense. Well, sometimes, you have to think about IF China's defense is actually that defenseless and China's offense is actually without a punch. One good example, China's air bases. As I have learned from some of our fellow posters, many of China's bases are super-hardened while none of the US bases in the area are. That would mean it's much easier for China to cause damage to the US bases than the opposite. Also, some claim that even China can damage US bases, it can be easily fixed. The same can also be said of China's bases. These bases can also be easily fixed. Many China's bases have been constructed to make bombing difficult, etc. etc. etc.
So again, I'm not attempting to predict which side will win a war. I don't think anyone can do that even at the beginning of a potential conflict, not even experts. General MacArthur who would be the expert of all experts thought he would win the Korean war in a few months, but ended up fighting to a stalemate. The same went with the Vietnam war. The US would not go to Vietnam thinking that it would lose the conflict. the majority of military experts believed that the war could be won in a few months. and look at the outcome... And what about Napoleon? another expert shown to be unable to predict the outcome of a conflict... So don't even think about predicting the outcome of a potential conflict just because you think you know a few things about weapons. My point is that China is a completely different situation and need to be dealt with using completely different strategies. Those who believe that one can use the same method for catching a chicken to catch a deer would be in a deep trouble in a potential conflict.