What was ironic about the Know Nothing Party?

The Know Nothing Party was a political party that was against immigration to the United States. The people in this party were concerned about the increasing number of immigrants coming to the United States. They were very concerned about the number of Catholics coming from Ireland and Germany that were entering the United States. When people asked them for what they stood, they often replied that they knew nothing.
The irony of this political party is that many of the people who supported the party were from families that were immigrants to the United States at some time the past. Their families came to the United States for reasons such as religious, economic, or political freedom. However, when other people wanted to come to the United States for similar reasons, they were opposed to these people having the opportunity to have a better life and to get more freedom. They wanted to deny other people the same opportunity that they were able to have.
https://www.u-s-history.com/pages/h140.html