Long simmering tensions came to a head this week when more than a thousand people packed a county board meeting.
"This country is being invaded no less than if hordes of armed people came across its borders," said one speaker.
"I fought for this country, across here, which one of you fought for this country?" asked another. "And now you're sitting down there trying to pass a bill that will -- you know what? Forget the bill," the man said, stalking off the podium.
"It's we the people of the United States, not we the illegal!" countered a third speaker.
The marathon session raged until 2:30 a.m., when officials unanimously passed what they call the nation's most aggressive crackdown on illegal immigration. The law:
"Eventually, I think what's going to happen is you're going to see a flight of illegal immigrants from Prince William County," said Corey Stewart, chairman of the Prince William County Board of Supervisors.
Nearly three dozen communities across the country have taken matters into their own hands and passed laws aimed at curbing illegal immigration. But there have been some unintended consequences.
Just over a year ago, city leaders in Riverside, N.J., voted to punish employers and landlords of undocumented workers and saw the impact almost immediately.
"People were ruled by fear," said David Verduin, who heads a group of landlords and business owners in the town. "A lot of immigrants stopped coming downtown, and even people from outside of town didn't come in because they were afraid."
Some businesses lost as much as half of their income, and immigrant rights groups sued, costing the city tens of thousands of dollars in legal fees.
A few weeks ago, Riverside rescinded its ordinance.
"We're looking at other ways to address those issues," said George Saponaro, the township's attorney.
In Virginia, they're pushing ahead anyway.
"We can no longer afford not to do anything about illegal immigration," said Stewart. "It has come to the point where it has seriously degraded the quality of life in the community."
Still, legal challenges are underway, and some stores already report a drop-off in business.