Seeing the large number of immigrants illegally entering the United States, proponents of immigration controls decry what they label the “open border” between the United States and Mexico.
I live in Virginia. I sometimes enter Maryland by crossing the bridge that spans the Potomac River, which forms part of the border between the two states. There is no border-control station at which Maryland officials require me to stop and be subjected to questions and have my vehicle searched. There are also no border patrol agents patrolling the border to ensure that no one is entering Maryland illegally.
