Everything else being equal, an immigrant will always out-compete a native on the job market. A native is working for money, an immigrant is working for money and access to a society that's better than the one he was born. It doesn't take a genius to realize the immigrant will always accept a lower wage than the native. Personal competence is irrelevant, the same job that an African will out-compete me as a native Brazilian is a job i will out-compete any American if i emigrated there.