Who Is Stephen Miller?
Homeland Security Secretary Kirstjen Nielsen abruptly resigned on Sunday.
Multiple reports have said White House senior policy adviser Stephen Miller was the architect behind her resignation.
Just who is Stephen Miller?
He is a hardline anti-immigration operative.
He pushed Trump to ask for $5-billion for his border wall.
Miller was previously identified as the driving force behind the Trump administration's controversial immigration policies.
He has been a rising star on the far right for years.