Before you take one line from Aquinas, which can be interpreted in other ways than in the manner in which you use it, take the many lines from Scripture that call us to welcome the stranger. I understand your concern about laws being broken, but the needs of the poor supersede these laws. That’s not my opinion; rather, it is the Word of God.
If you read Matthew 25, for instance, you will see who it is we are welcoming — the Lord himself. My experience through many years of solidarity with migrants (both legal and illegal) has taught me that to encounter the migrant is to encounter Jesus. Don’t deny yourself this opportunity to get to know God by loving your neighbor. Go to the migrant and help him and learn from her and you will see God. In recognizing that you are your brother’s keeper, you will be blessed with a profound sense of God’s presence in the least brothers and sisters.
I promise you.