I did not say illegal aliens are citizens. Their children born here are.
Everyone here is subject to jurisdicton of the United States. There are a few exceptions. They are children of foreign diplomats, foreign officials with full diplomatic immunity, and Individuals on foreign public vessels or occupied foreign territory.
Here is a link to persons subject to jurdisdiction of the United States.
§ 515.329 Person subject to the jurisdiction of the United States; person subject to U.S. jurisdiction.
https://www.ecfr.gov/current/title-31/subtitle-B/chapter-V/part-515/subpart-C/section-515.329
§ 515.330 Person within the United States.
https://www.ecfr.gov/current/title-31/subtitle-B/chapter-V/part-515/subpart-C/section-515.330