If they simply obtained warrants, arrested people, treated them with dignity, let them have a trial, and then deport them, then the only objection would be why $50B is being wasted on rounding up non-violent migrants, or why the business owners that hire them aren't in prison as well.
You can't claim that your goal is to enforce the law, and then find pesky little things like due process, and warrants inconvenient.
After decades of being conservative and having their politicians sell them out, Republicans got really angry and gave up on conservatism in favor of radical destructionism instead. Rather than finding better politicians to represent them, focusing on workable policy (go after the employers), generally being less gullible, and so on, they decided the appropriate response was to throw the whole idea of Constitutionally-limited government in the trash in favor of a strongman con artist promising to magically solve it all. And they've convinced themselves they're on the right path because it makes "liberals" mad. Where of course a "liberal" is anyone concerned by throwing our Constitution in the trash.
Something a lot of people aren't considering is that a dictator ship might become a reality and these people will succeed, the US will decline but still remain a powerful country but with constant internal strife and divisions. The real goal seems to be curbing American influence overseas, and containing the US, just like the US tried to contain Russia and China for decades prior.
The US military/intel community literally used sitcoms to influence the middle east in the 2000's. What goes around...
I think this is the real outcome of having so much debt owed to foreign countries. The political kayfabe all focuses on it like it's some mortgage where other countries will foreclose or whatever. But there is no mechanism for that to actually occur. What it does allow those foreign countries to do is to buy up significant chunks of the US, and then exert the control that customarily comes along with ownership.
[0] this is also why they'd constantly rage-farm about immigration, but then turn around and facilitate the supply of cheap illegal labor