The best reason to raise Northern Virginia's sales tax is not to pay for new roads, not even to extend Metrorail to Dulles Airport. The best reason to vote Yes in November's referendum is to start correcting a 70-year-old wrong.

You wouldn't think Virginia history would have much bearing on whether a 21st-century Edge City should build highways and train tracks. But Virginia is a special place, one that historian V.O. Key once described as a museum of democracy that boasts the trappings of government by the people, without the substance. One man is remarkably responsible for those shortcomings: Harry Flood Byrd, whose Byrd Organization ruled state politics for half a century.

Byrd first won fame by standing up to state government in a 1922 version of this fall's referendum, a battle over state bonds for new road construction. Counties were in charge of building roads in those days, just as local government handles roads in almost the entire country today. But cars were just becoming the main means of transportation in the '20s, and Virginia needed a whole lot of new roads.

Byrd knew the roads were inevitable, but loathed the idea of Virginia going deep into debt. After all, the state was still saddled with debt incurred before the Civil War. So Byrd campaigned against borrowing money to pay for roads.

In 1932, with counties scrambling to survive the Depression, Gov. Byrd pushed through the Byrd Road Act, which put the state in charge of all county roads. "The counties came to the state and said we're doing schools and roads and we can't afford to do both," explains John Milliken, chairman of the Yes campaign in this fall's sales tax referendum. "And the Byrd Organization said, 'Hmmm, highway construction, what a good idea.' "

So, to this day, the good old Virginia Department of Transportation controls road decisions even in urbanized Northern Virginia. (There's more on this and other aspects of Virginia geography and history in an online course developed by Charlie Grymes of George Mason University, worth a visit at www.virginiaplaces.org.)

VDOT, of course, is the bureaucracy that everyone loves to hate. It is famously unresponsive to Northern Virginians, unsympathetic to advocates of smart growth, and unable to adjust to the needs of an urban area. So the Yes campaign in next month's referendum sees this vote as a way to "gain control of our revenue stream so it doesn't have to be laundered through Richmond," as Milliken puts it.

"There's a gut, visceral desire to say to Richmond, 'We have outgrown the Byrd Road Act, and it's about time we took control of this ourselves,' " he adds.

Milliken is right. Even though the sales tax increase would not wrest authority over construction or maintenance from VDOT, it would create a local body of Northern Virginians who would set the transportation agenda for their fellow citizens. That's real progress.

Amazingly enough, some opponents of the sales tax concede the merits of the local control argument: "I'm very sympathetic to the idea that this referendum gives us a chance to control our own direction as a region," says Stewart Schwartz, whose Coalition for Smarter Growth is leading the No campaign. But Schwartz, who lives in Alexandria and walks to the Metro each morning, says the local autonomy argument just doesn't hold up against the list of projects that the sales tax increase would pay for -- a list he views as too heavily weighted toward more and bigger roads that would feed new sprawl.

That list includes more than $1 billion in transit improvements, the Yes side's attempt to win over environmentalists and smart growthers. But the transit sweeteners haven't eased the No side's nightmares of outer beltways and western corridors and a techway bridge across the Potomac.

In the end, the decision on the sales tax comes down to your vision of the Washington area's future -- not just how much time we will spend in traffic, but what our neighborhoods and houses will look like, how we'll spend our weekends, where we'll work. I'll explore the contours of our future in my last look at the Nov. 5 vote.

Join me at noon today

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