They can do, they sure does have the resources to do it as well, but thing is that if China wants to become a Global super power and make the world fear them they have to fight a war, practice and exercise wont cut in. Having fancy and new weapon system will do them no good, because with the combine resources of NATO Americans will outmatch them for next 50 years easily. China is literally just issuing threats while no major action has been taken by them, I mean look at Russians their economy was worse than China, their military condition/equip was old as Qaim Ali shah and yet they Attacked Ukraine, yes they are paying heavy price for it but they will earn the respect from their enemies (NATO/America), the lack of fighting will is why western countries although say they are worried about China's rise but no one take China Seriously.