If you honestly reflect back on your race, your ethnic background, etc., you will realize that when it comes to immigration and immigrants, we all stand on wretiched ground. There are so many examples that will fit us, but here are a few to reflect upon:
Jews were immigrants into Europe. How were they treated? There was anti-Semitism from the beginning. And six million Jews were murdered by "Christian" Germans. Yes, there were a few people who fought to save the Jews, but for the most part, it was the viewpoint against the "immigrant" Jews that led to a policy of extermination. Jewish immigrants to Europe resulted in the largest acts of genocide in history.
Europeans came to the New World, and for the most part they found innocent, welcoming Native Americans. Read Christopher Columbus and his daily logs. The early Europeans brought "Christianity" and felt they had the God-given right to treat the Native Americans as they did, and in the process they practiced acts of genocide. Ethnic Europeans almost destroyed entire cultures of American Indians.
A huge wave of immigration took place when Europeans loaded Africans on slave-ships and brought them to the Americas. The African slaves were treated like animals, and as many as 1/3 died in transit. Europeans brought the slaves to a welcoming bigotry in America. The history of slavery and its aftermath in America is one of the most savage, brutal, and inhuman acts ever. It should be noted that slavery ended in other parts of the New World long before it ended in the United States.
In the aftermath of World War II, many Jews immigrated to America [many had been refused entry before the War]. It is a great lie of American history that they found a welcoming nation. Anti-Semitism in the United States was rampant after World War II, but many Americans think they were greeted with open arms.
During the colonial period and afterward here, the emerging United States of America literally stole huge areas of land from Mexico. Now we act as though we were totally innocent in that area. And oddly, we have extreme and hostile attitudes toward "immigrants" coming from Mexico. We act as though a moral and ethical U.S. suddenly appeared in the current land area and we have a right to protect it from all "other" people. How we obtained the current borders is rarely questioned.