In modern times there have been brief shooting conflict between China & Vietnam in 1974, and 1988 [1], and there have been numerous incidents since.
[1] http://en.wikipedia.org/wiki/South_China_Sea#Territorial_cla...
Plus, the attacks happened around Spratly islands, 2 days right after Shangri-la Dialogue, with the participation of top military bosses, including Robert Gates, where China promised to use peace talks to resolve the problem.
My 2 cents here:
1. China has always been a world of its own, it acts by its rules and what it promises is just what is says, what it does is another thing.
2. China has become BIG, and worse, it IS aggressive. We'd better be prepared for a coming war, be it cyber or economical or traditional.
We might be under a much bigger threat than what the media could convey, like that picture by David Gothard http://si.wsj.net/public/resources/images/ED-AN742_clarke_D_...
As for your points 1 and 2, do you think people don't attribute those to the US as well ? Point 1 in particular falls into what is called unilateralism - a pervasive notion in the political discourse of the US since their inception. My point is not to fall into superficial anti americanism: it i simply in the best interest of the US to act this way, and most countries pushing for multilaterilsm are countries without the power to act differently anymore. But moral, fairness has absolutely nothing to do with it.
China are aggressive in what they believe is 'their' territory, and nothing else. They have no (modern) history of invading or even being involved in other conflicts around the world. Most [large] countries could not boast a similar history.
On the UN security council they veto most aggressive action the US/England/EU press. If further pressed they generally abstain from the vote. Other than territorial disputes where do you get the idea they are 'aggressive' ?
China is out to protect it's interests just like every other nation. The worry is, they are big, and CAN protect their interests. The western super powers are not used to being challenged like this.
Another point is, I can't remember who (pretty famous analyst) said this, but something like: "There's nothing wrong with China's getting richer and stronger. The only problem is China was once depressed by other countries like Japan, England... And like a child, when he grows up, he will take _revenge_ "
So China is not just-like-every-other-nation like you said