Irish Americans made up about 11 percent of the U.S. population in 2000, with a reported population of 30.5 million. They were the fourth largest ancestral group in the United States, after German Americans, Hispanic or Latino Americans, and African Americans. Irish Americans have spread throughout the United States and have long been assimilated (absorbed) in the mainstream culture. It is difficult, therefore, to imagine that 150 years ago, Irish Catholic immigrants faced severe discrimination (unfair treatment based on racism or other prejudices) when they arrived in the country. Many of the early immigrants suffered wretched living conditions and performed backbreaking work for low wages in the hope that their children would have a better life. Some historians have observed that the experience of the 4.5 million Irish immigrants in the nineteenth and twentieth century was typical of the American immigrant experience in general. The American Immigration Law Foundation...