Yes, I am. And as far as one-liners go, that one barely made it past the start gate. But I can see where you might have been going with the triple question marks. The non-interventionist policy is shifting and in doing so, China has two recent (last 100 years) models of foreign policy to choose from. First is the semi-isolationist policy which they've held to since 1949, exception being the Korean War. However, it's become clear that they will need to secure their global economic assets with more than just words.
So, they must adopt a more interventionist policy. And who has used interventionist policies effectively in the past 100 years? The US, the UK, Japan, Germany. I'm not saying that they're going to start blowing up railroads or sending foreign contingents to fight for causes they support. But they will assert themselves whenever and where-ever they feel they should. Because the one thing they can count on is that the US does not want push to come to shove because a war with China would ruin everyone's year. So China feels fairly confident with prodding its neighbours with a pokey stick. Prodding mind you, not shelling them because of suspicions like North Korea.
I'm from Singapore. I'm a lot closer to China than you are. I don't particularly see the threat as being all that large. Your comparison fails to account the vast differences in government. Japan began its modernisation in 1860 with the intent of being able to militarily oppose and defeat the western powers. By the 1930's, any form of moderate civilian government had been ousted by military leaders. China is not currently being run by military leaders and its focus is economic dominance. Its younger officers are not running around promoting war and plotting against the government (see Mukden Incident). Nor is China annexing and colonizing areas by force. The fact that there are even talks and disputes shows that China is not resorting to the military as its answer the way Imperial Japan did. Military assets are simply a means of backing up claims and providing security.
Though I note one parallel that you may not have come upon. Both China and Japan were forced open (to be exploited) by gunboat diplomacy. I wonder who gave these Asian nations the idea that might makes right. Again, colonialism finally coming back to bite the west in the arse.
My question still remains, why is China's ascent as a superpower considered so dangerous to the West? Is it only because the US and its allies want to remain top dogs? Or something else?
China's defence spending is nowhere near that of the US. That alone should prove that they're not pouring money into a rapid military mobilization like Japan did.