The clearer picture
It's ironic that one of the best posts on this thread is the one that hasn't drawn any comment. Check out Tom's reply to Daniel above:
While immigrants from Africa and elsewhere are no doubt poor in France, when I was there, they seemed to be the sole repository of anything resembling an entrepreneurial spirit. They run all the souvenir stands, and most sidewalk vending outfits. During the heat wave, they were doing yeoman business selling water bottles out of tubs of ice on corners all over Paris. Lord knows they got enough of my money.
In Nice, on the beach, one guy was selling crisp watermelon slices out of a cooler, and good ones, too. If fish started raining from the sky, you would turn around and you can bet one of these guys would already be standing there with a fried fish concession.
Compare this to the "entitlement philosophy" that seems to pervade native Frenchmen.
In thirty years these people will probably own Paris, and it may be better off for it.
It isn't usually the case that immigrants are destitute in their homelands, but rather that their homelands become destitute and they flee to survive. It's usually the case that their homelands are being destroyed by a kleptocracy or a deranged government deliberately fomenting genocide, as happened in Rwanda.
If they can't make it in a place more at their level, how are they going to fair better in a 1st World country?
You have it exactly backward. As Tom observes, immigrants generally thrive when they go to the First World, so if they're seeking their own level, they're clearly seeking a higher level.
Tom's last sentence bears repeating because it bears on anti-immigrant bigotry: "In thirty years these people will probably own Paris, and it may be better off for it.". That's what immigrants always bring to their new lands. It's what they brought to America. You might call it "mongrelization", but I'd call it "hybrid vigor". I welcome the new blood.