Well if we have annual quotas that our economy and social service structure is supposed to be able to handle, and if those quotas are vastly exceeded by criminals outside our immigration process, then maybe on occasion a cooling off period could be a good idea. Nonetheless, he is not against immigration, nor am I.
Given the massive immigration, legal and illegal, that we've experienced in the last 20 years, it is probably a good idea to have a moratorium on all immigration for at least a few years. We could work towards unity as Americans, and more social cohesion. "E Pluribus Unum."
Of course, the "diversity" Establishment would never allow this, since America is all about celebrating "difference" these days. Or else.
We need to change our legal immigration policies as well. We are taking in more than a million people a year and most of those are the result of chain migration, which reduces the diversity of immigrants and leads to problems of assimilation and balkanization.