Last time I looked this world was round people. It's the animal instinct in the human that makes him tribalistic & territorial. It's also the animal instinct that makes him racist or xenophobic, the sooner we evolve enough to realise we are all one created by God, whoever that God may be, the better. I realise how comfortable it is for people in first world countries to frown upon illegal immigrents who have, basically, nothing but the clothes on their back, seeking a better life in a place that, according to that counties constant advertisments, is richer, but I urge you to sit back & think, what would you do?
It was only a few hundred years ago that the American's European ancestors did exactly the same damn thing. It wasn't too long ago that the British created an empire spanning the globe, not by sneeking in a country through a back door, but by storming it & killing all who opposed. Same goes for every other country. If you are opposed to immigration in America, you may pack up your suitcase & sail to Europe. If you're opposed to Immigration in Britain, you may first apologise, individually, to every country you have raped & pillaged THEN sail for Germany or Denmark.
Fact is, they are no different than us & our ancestors, it's just different times, different means & different reasons.