Remember when National Airport was and still is located in Arlington? Then why do the news reporters still say "This is (their name) reporting from Washington DC?

People seem to forget that we are a separate entity. Apparently we are a vassal state of the District. What really pisses me off is when I hear people from out of town talk about how D.C was attacked on 9/11 and I have to remind them/ or enlighten them of the fact that the Pentagon is in Arlington.