Immigration is a make-work project for government. They need to keep full the government schools, hospitals, and jails, and keep the bureaucratic empire expanding.
An unrecognized impact of socialism versus traditional family-ism, is socialism removes the return on investment for the time and expense of having children, and raising them to their fullest potential. Developed countries don't stop raising big families because they are developed, but because they start socialism. Young people are freed from supporting their aging parents financially, but in trade, are enslaved to pay for the government's Ponzi schemes.
And let us not forget the origin of this immigration wave. We launched the Arab Spring in Egypt. Then it spread. NATO decided to attack Libya and fly top cover for Black Flag waving Al Qeida. At the same time we launched our attack against Syria with our Syrian rebel army/FSA/Al Nusra/ISIS revolt.
Our sicko neocon machinations are the root cause of this who thing.