What are the cons of illegal immigration to the US?

More immigrants means more opportunity for terrorists, drug dealers, and other criminals to enter the country.

Immigrants, especially the poorer ones, consume a high amount of government resources (health care, education, welfare, etc.) without paying a corresponding high rate of taxes.

The national identity and language is disappearing. The great "melting pot" is being replaced by divisive multi-culturism

also less-skilled American citizens earn less money and have fewer job opportunities because they must compete with immigrants in the job market.