Are China's claims to the majority of the 'South China Sea' unethical?

To be clear, I think they are. But what about all the other claims? Most territory it seems that is currently owned/claimed was usually acuired with at least a fraction of malicious, manipulative means. China’s leaders, IMO, understand that the Earth, and it’s resources are finite. They are making a claim of a vast swath of territory because they are basically ‘goin all in’, and daring some country to resort to all out war with them to halt their actions in these disputed waters. Is that just looking out for your people, or is it war mongering, and irresponsible ? If real life was a video game I would (without bias) think they are smart in trying to bully the territory away when the opportunity is there. But this is really reality…