This is warning of what happens when a nation isn't obedient to God. The following is another warning specifically mentioning aliens :
Malachi 3: 5 "So I will come near to you for judgment. I will be quick to testify against sorcerers, adulterers and perjurers, against those who defraud laborers of their wages, who oppress the widows and the fatherless, and deprive aliens of justice, but do not fear me," says the LORD Almighty.
If "aliens" owned property according to the law, they couldn't just have it stolen.
But if they stole that property, it was by all means just to give it back to the original owner.
I suspect you know the difference between a stranger and millions of illegals. I can easily find just as many verses where God told the Israelites to not mix with strangers or aliens. Obviously you must also agree that the Israelis must not enforce laws against Palestinians. We should open our borders to all people no matter what disease they have, what nation they come from and let them devour our inheritance in our presence. Is there a point a Christian can protect himself? This is not one stranger wandering the city, this is 12 million invading America with no intention of honoring our laws. Do you really think God is instructing the Jews to entreat aliens who went to Israel to break the laws of the land?
Justice to the illegal alien would be to deport him. Would it not?