Although my discussions with her took place 15 years ago, the concepts behind them still stand true. It is indeed a fact that immigration policies in the U.S. were decidedly European before 1965. In other words, if you weren't white, you weren't right, and you weren't getting into the U.S. Before 1965, immigration policy was structured around a quota system where the determination of who would get immigration visas was based on the percentage of your ethnic group in the existing U.S. census. Since the overwhelming majority of people in the U.S. at that time were of European descent, that meant the overwhelming majority of people offered immigration visas would also be a European descent. Consequently, before 1965, approximately 93% of all immigrants in the U.S. were European (white). So, in other words, no matter how smart, how good looking, how patriotic you were to uncle sam, if you were of color, tough luck getting a visa to enter the U.S. It wasn't going to happen.
What changed was the great deal of pressure activists within the civil rights movement put on the legislature to broaden immigration policies. This work consisted of challenging the racist foundation of immigration policies in concert with efforts to challenge racist practices in all levels of governance. The result of this social pressure was the 1965 Immigration and Naturalization Act, or the Hart Celler Act, which abolished the quota system and changed the focus of immigration to uniting families and providing a human rights service. This change in focus greatly benefited people of color who's lands were the target of imperialist wars and occupations. As a result, the immigration gates were opened for people from Vietnam, Laos, the Philippines, Azania, South Africa, Ethiopia, Somalia, Sudan, Iran, Mexico, etc. This change in immigration focus has had a dramatic impact on who is immigrating to the U.S. For example, in 1950, 60% of all immigrants that year were from Europe. In 1990, according to the census, 90% of all immigrants were from Asia, Africa, Central and South America. In that year, a whopping 35% were from Asian countries. Those figures have tipped dramatically as unstable economic policies from imperialist trade policies like NAFTA and GATT have terrorized the people's of Mexico, El Salvador, etc., into fleeing chaos to come to the U.S.
The point is the ability to come to the U.S. shouldn't be seen as any great moral offering by U.S. capitalism. It is instead the result of mass policies of destabilization in countries around the world in imperialism's constant pursuit of riches and control of land resources. Even still, the racist policies that have always defined this country would never have supported the masses of immigrants of color coming here without the push of those freedom fighters who fought to challenge systematic racism in every space of U.S. policy; domestic and international. So, despite the propaganda you receive telling you to thank this country for being here, what you folks of color who's families have immigrated here should be doing is thanking the masses of Africans who shed blood and opened the door for you. You should learn to look at uncle sam for exactly what he is. The terrorist that sabotaged your country in the first place, thus making your ability to stay and prosper there impossible while he posed as your friend and acted as if he was offering you safety when he has never wanted you here in the first place.