Is China next to become the most powerful nation?

It is predicted that China will be the world’s most powerful nation by the year 2050. China has remained one of the top five most powerful nations in the world. Second after the United states. Because of its economic growth since 1992 China is expected to over take the Unites states to become the worlds largest economy by 2030. Could this really be possible? And why exactly is the United states losing power, well after the 1920’s crash of the stock exchange, the US economy grew because of the manufacturing industry and their vision to invent new products. In the 1980’s the US lost its vision and the economy became based on a bubble of speculations. People started borrowing and spending beyond their means. Also the wars entered into by the United States in the 2000’s has been another factor to it’s down fall in its economy. In contrast to China that have taken over the manufacturing industry and has based its economy on the fundamentals of what a growing economy should be.
Also China has not entered in the race of armaments in competitions with the US and Russia. China is only developing and investing in armaments to protect itself in case of an attack by a foreign nation, in line with its own nature and history of not being interested in becoming an empire and conquering other lands. So what do you guys believe? Can China really become more powerful then the United States?