Immigration is good for the economy. This is a historical truism. It is when people leave a country, taking their skills, their labor and their wealth with them that a country suffers.
People immigrating? Send us your hard working, your skilled, your greedy yearning to become wealthy. Because those folks- whether they are working in the fields, doing research or construction- are making our country more wealthy.
Employment is not a zero sum game: If I do yard work for a living, then in addition to what I need to survive, I’m buying rakes and shovels and seed and fertilizer and all of that helps to employ the people selling, transporting, and producing those things, not to mention the people who mined or cut or harvested the raw materials.
If I work in a lab and test the effectiveness of drugs, my analysis either makes the fortune of a great many developers, or opens up the market to many more.
If I am planting seeds and harvesting crops, those crops will profit not just me, but my employer, the truckers bringing the crops to a warehouse, the warehouse attendants, the truckers bringing the food from the warehouse to the grocery store, the grocers, on through to the bag boy and shopping cart collector.
The point is this: until we reach a point where we cannot support any more mouths to feed (and this is a planetary concern, not a regional one) then more people working = more opportunities for other people to work.