You import the third world you become the third world, people make a country, third world citizens don't come here and instantly become civilised, they bring their mindset, upbringing, and mannerisms with them, they bring the 3'rd world.
I remember people in London who did a bit of wheeling and dealing who used to hate getting bundles of foreign paper (Scottish notes), they wanted real money,you could always tell if something had ended up north of the border back then.