We can't be guardians for the entire world.
I remember working in counter fraud and reading arrest sheets, some illegal immigrants were found with over 50 passports and loans/credit cards in the name of each fake 'persons' name. When they whittled the passports down to find out how one of them actually got entry into the UK he had claimed asylum from his home country of Pakistan because his 'sister was stoned to death in the street'.
We ended up uncovering a network of around 800 people involved in credit fraud, I left a few months later and I was told by my old colleague a coupmle of years after that they never managed to get a single prosecution on any of them for jail time. We continue to harbour these people because Europe tells us we simply cannot send them back to their country.