The situation in countries in Africa is that they have something like 1 job available for 10 people. 1 job has to support 10 people. They don't stop breeding because they can't afford children, they make childrens as an affirmation of life.
The more people that come from any country like that to north america, the harder it's going to be for people that are already here.
They won't settle for what you don't want to do, they will go to university too. They will be in direct concurrence to whoever gets a salary from an employer in the USA. They are and they will steal your job, plain and simple.