By now there is a certain weary tone in the voices of those who joust over transportation in Northern Virginia, and no conversation ends without mention of the Manassas battlefield that sits smack in the middle of the contested turf.

The two Civil War battles fought there were more straightforward and a lot shorter than the decades of warfare over the best way get from here to there in the ever-more-congested part of the state. The battle was rejoined Wednesday in Richmond on a point that everyone agreed was “a gray area” but that all still assumed must be important because it seemed to be so to the other side.

The issue at hand: The Commonwealth Transportation Board’s proposal to designate a swath from Interstate 95 across Prince William and Loudoun counties as a “Corridor of Statewide Significance,” making it the 12th place selected for the label since the state legislature created the designation two years ago.

This move is either recognition that north-south mobility is needed in a region that now moves on an east-west axis, or it’s an attempt to accelerate construction of a controversial parkway linking the two counties and ultimately connecting to new Potomac River bridges to create an outer Beltway around Washington.

The true significance of the designation — approved by the board in a voice vote Wednesday — will only become clear over time.

“Essentially, what this will do is look at this as a corridor to put some planning money into it,” said Sean T. Connaughton, state transportation secretary and a veteran of Northern Virginia transportation warfare as former chairman of the Prince William County Board of Supervisors. “It is no specific road; it is no specific plan. We will look at roads, transit, buses, bike paths and even pedestrian accessibility.”

To those who advocate measured growth around existing communities and development of public transit options to serve that growth, the new corridor points to one objective.

“They are jumping to the conclusion that a major circumferential route on the outer edges of suburbia is the solution to our transportation needs,” said Stewart Schwartz, executive director of the Coalition for Smarter Growth. “We don’t think that building a north-south route is justified in a region where the east-west traffic is three to 10 times higher.”

Schwartz sees the ultimate goal of the corridor effort as a bridge across the Potomac east of Leesburg or in Great Falls that would require highway construction on the Maryland side to link with Interstate 270 or the Intercounty Connector.

Enter Bob Chase, another transportation war veteran and director of the Northern Virginia Transportation Alliance.

“It doesn’t involve an outer Beltway, though I wish it did, and it doesn’t presuppose a bridge,” Chase said. “The need for north-south mobility has been documented time and again, and this is about as benign a step as you could take.”

If Connaughton, Schwartz and Chase are central players in the modern staging of the transportation debate, there are hundreds of others who have devoted thousands of hours to the discussion over the past 30 years.

In addition to the outer Beltway proposal, which still lives in a few hearts but generally fell out of favor in the 1980s, there have been a number of studies and proposals to link I-95 with a significant roadway through Prince William and Loudoun.

The intent of those pushing for such a highway has been to better serve Dulles International Airport and the rapid expansion around it. A Tri-County Parkway that would run east of the Manassas Battlefield to include Fairfax County and a Bi-County Parkway that would run west of it both still are on the planning boards.

Each of the three counties has its own transportation goals, and they don’t always coincide or embrace the views taken by one side or the other in the arguments of those like Schwartz and Chase (or the Chamber of Commerce, or the Sierra Club, or the Metropolitan Washington Airports Authority or the Southern Environmental Law Center) who take the regional perspective.

Chase called Wednesday’s vote “a major step forward” but acknowledged it “isn’t the end of a process; it’s the beginning of one where you go about evaluating a number of options.”

Schwartz worries it’s a sign that power over local decisions is being concentrated in Richmond and “leaving out the local bodies.”

“Twenty years ago,” Connaughton said, “this move might have been controversial. But today, when you look at population growth, we need to look at mobility between Prince William and Loudoun and start doing some planning.”