This document summarizes Stephen Miller's rise to prominence as an immigration hardliner and senior adviser to President Trump. It describes how Miller was shaped by growing anti-immigration sentiment among Republicans as immigration levels increased and shifted demographically. As an aide to conservative members of Congress starting in his early 20s, Miller helped promote restrictionist views and policies. He advanced within the Trump administration by taking increasingly hardline stances on issues like border security and refugee admissions. The document analyzes how Miller embodied and advanced the anti-immigration movement as it gained influence within the Republican party.