Which is bigger, the Immigration Bureau or the Embassy?

According to immigration data, in 20 10, about 45 million China people lived abroad (ranking first in the world). 20 1 1 year, about150,000 China people obtained the permanent residency in other countries. Most of them immigrate to the United States, so more than one million people want to immigrate to the United States every year, but it is impossible for all Americans to immigrate, so there are strict restrictions, mainly because there are too many people in China. But the immigration system in the United States is the same, depending on the attitude of immigration officials towards China.