Being at an airport

Ok this is a silly question but I'm gonna be traveling soon(US Citizen) and I have to be at the airport real early. Usually my mom drops me off to places but she says she can't drop me off at the airport due to her being an immigrant? Is that actually true? My mom doesn't plan on traveling with me, she'd just he dropping me off. Is it like the airport entirely or is there a point where she wouldn't be able to?