Why Is Anti Immigrant Sentiment So High in the United States?

Government bureaucracy is bloated, expensive and absolute waste. Immigration department is the stupidest of all emigration departments in the world. I don't think a government agent is smart enough or in any way informed enough to have an idea about how many people should be able to come into a country. And iv trust the wisdom of the crowds and supply and demand far more than i trust a government bureaucrat. But, but what's the problem? Why is anti imigrant sentiment so high in the united states?"