Really? Jealously? When I was a freshman in college I worked a lot of jobs and had Africans working and all were really hard working and a lot held respectable positions in nursing positions, doctors, pharmacists, u name it. They all seem to value education and wanted to do well.
Now the American blacks are a different story 
Yeah, it's different. When people of different ethnic groups talk amongst themselves you see the true feelings.
Many Africans that come to school in the US believe black Americans waste their opportunity, and also believe that they are better because they are "pure" African...like how many Euros think that they better than yanks.
But, these same Africans come from poor countries that are rich in minerals. So, why have these same countries gotten their ish together?
It's a jealousy of Americans having access to certain things. And harsh criticisms of lack of hard work....yet if people in their country worked so damn hard, why are the people poor, lack education, etc.
Same thing for the West Indians.
Black people have a shameful self hatred of one another. In college I was friends with Africans and Caribbeans.
Now, I will say this. American culture as a whole tends to emphasize "slackerism" especially among men.
And when many who are 2nd or 3rd gen Americans who are "Americanized" tend to exhibit the attributes that they claim Americans (or Africans claim American Blacks) have.
