His policy will cost 600 to 800 billion to enforce. Our economy thrives on the labor of these immigrants. Losing 11 million workers will reduce the gross domestic product by 1.6 trillion. Particularly the agricultural industry depends on the cheap labor of immigrants so as farmers lose income this will result in a drastic rise in food prices... also these immigrants whether they are legal or not spend a large portion of money in the local businesses where they live.
Well that's assuming all of the guesstimated 11 million undocumented immigrants in America are working. In fact it is illegal for them to work most jobs, and has been illegal for some time now. As for farmers, actually farmers do it the legit way from my understanding via the guest worker program. The guest workers are not immigrants, they are documented seasonal workers that come into the country and then leave and go back to their homelands as they are contracted.
Also keep in mind in the Trump ideal world we would be growing good jobs simultaneously by implementing absolutist economic policies like protectionism and raising tariffs. Kasich also has similar views on both immigration and trade and job growth, but Kasich takes a more humane Christian approach in my opinion. Trump's approach is legit though. Plus I think Trump has the drive that even if he don't get all that he wants he'll at least get some action done on the issue. That's half the battle really, a lot of these problems aren't that impossible, there's merely no political will to get it done. Trump has that strong will and drive that we need to get stuff done and Kasich has the mind and the experience and wisdom for how to get stuff done. Hard choice really between the two.