Making It in the "Land of Opportunity"

About a week ago I received a phone call from a friend of my father's. He has been living in the US with his family for 7 years or so but has not been able to find a job matching his qualifications from Bulgaria. The longer I spoke to him, the more I contemplated the absurdity of the situation. A graduate degree and years of experience from another (I guess, non-Western) country apparently count for nothing. But how long do you stay before you make the decision to call it quits and return home (where, granted, quite a few things have improved over the last seven years)? Do you keep trying in the hope that with the next set of applications you will succeed? Do you stay because your son would have better opportunities here than back home? Even if it means that you have to drive a cab or deliver pizza? I guess the answer to those latter questions would be "yes", but it still felt strange to think that someone twice my age, with much more work experience than me, someone I consider my father's peer, has lower chances in the US job market than I do. I guess that's how the system works. Or perhaps there is an age limit to "making it" in the US? If you arrive after you've passed it, you have no chance.