I feel like this somehow has to be done before they come into the country. I'm all for immigration and agree the country was built on it, and many immigrants have helped the country, but it feels like these days many are inside of the country (without being vetted at all) and posing a burden on local resources without contributing to taxes or otherwise, while all of this is happening for (at least) 5 years? This is assuming they apply and don't just find ways to make it on their own on the streets, which also isn't what we want. When people get background checks just to work somewhere, they're usually not living in the building until they are cleared... there must be other safe places (maybe ally countries?) we can have them go until they are cleared?
Among other things (like which country would agree to this?), there are laws that establish due process for asylum. And Trump killed the immigration reform bill, which would have reduced the asylum case backlog with a combination of more resources to process those cases and more authority for the CBP to turn people away at the border. Trump should know that immigration laws have to followed (or changed) because his own executive order attempting to circumvent the law was shot down by courts in 2017... or 2018 or whenever that was.
The bottom line is, regardless how you feel about immigration, Trump and GOP are
not going to solve any of the problems with it. They will milk the publicity as much as they can and then forget it until the next election when they can use it again.