In cases such as those involving Stonehenge or the Dakota Access Oil Pipeline, how can we find the right balance between protecting important sites and meeting the demands of a modernized population?

Albright: I tend to look at the question in a different way. The central question here is: ‘What makes a place important and to whom?’ On the flip side, ‘Why is the alteration of the site important and to whom?’ Any development project is going to involve coalitions of stakeholders who organize around a shared interest. Which coalition wins is ultimately a question of power. Ideally, opposing coalitions can negotiate and come to a resolution that is satisfactory to both parties. But in situations in which one group has significantly more political power than another, satisfactory resolution for both parties is unlikely.

Vicino: I tend to think of sprawl as a social process, a political process, an economic process, and a physical development process. The social and political processes are the factors behind why sprawl happens, and are often rooted in class and race segregation.

Overall, though, this reminds me of historic preservation debates. In the mid-20^th century, during large-scale urban renewal programs, some historic neighborhoods were almost completely bulldozed to make way for new development. On the physical side, there’s some value to preserving a property that has a historical legacy; there’s some cultural appreciation there. So, the city planning movement in the 1970s and ’80s tried to respond to that by building strong historic landmark laws.

When you’re thinking about balance, it’s crucial to articulate the values that any one government or society has in its development, whether that be open space protection, preserving clean water, etc. Building strong political support for declaring those values can be tough when we disagree over what those values should be.

How are land-use laws in the U.S. different from comparable laws in other countries?

Vicino: In the U.S., land use is controlled locally, whereas for most of the rest of the world, it’s controlled federally. These questions of who controls how land gets used are important for how communities develop. By doing it a local way, the local democratic institutions control the social and political side of urbanization and sprawl, with little consideration given to a broader, regional plan for development. This is why you’ll see something like what we have here. Brookline is relatively unfriendly to affordable housing, meaning that Boston has to carry the burden of that development. Paris, however, is a place that follows a regional growth plan, and is a good example of large-scale, compact urban development.

The issue with Stonehenge comes back to the need for these types of policies. The development of London has grown out so much that now it’s growing into places that were formerly rural, so even though the area has value and legacy and history, this makes it a vulnerable site. They need growth management policies to address these types of concerns and values.

At what point—if at all—might the U.S. and other developed countries draw a hard line in expanding infrastructure? What factors might contribute to our reaching a point where expansion no longer makes sense or is not even feasible?

Albright: Regularly, development projects involve the relocation of cemeteries. Cemeteries! Final resting places! This is the case with the Dakota Access Oil Pipeline, with the expansion of the O’Hare International Airport in Chicago, and with the building of the Quabbin Reservoir that supplies drinking water to Boston. There is nothing that can stand in the way of development except for economic incentives. Even human remains or sacred artifacts don’t stand a chance. Ultimately the only thing that will prevent expansion is if there is no economic or political incentive to expand. If gasoline prices go up to a point where individual consumers can’t afford to commute by car, the demand for sprawl will decrease and developers will be less likely to build.

In the past, eminent domain has been used to demolish entire neighborhoods. We have to look no further than Boston to see evidence. The entire West End neighborhood was bulldozed to make way for redevelopment. This comes back to the age-old question, Cui bono? Who benefits?

Vicino: There are areas, such as Portland, Oregon, and Minneapolis, Minnesota, that have very progressive growth policies in place. These reflect the political culture of an environmentally- and green-friendly mindset.

Elsewhere, I think we’ll find that when everybody can collectively identify that we’re one integrated region—that we’ll all lose growth at one point if the environment is so bad that we can’t breathe the air, or if the economy is so bad that we don’t have jobs—when the problems are bad enough that we can all agree they’re collective problems, then we’ll work together to get something done.

Through your research, have you noticed any trends in the way cities and suburbs grow and expand as many areas become increasingly land poor?

Albright: A dominant strategy has been the infilling or right-sizing of sprawl. Land that is being underutilized for things like parking lots is being redeveloped into dense mixed-used development. In areas that are already built out, one of the few options is to build up. There are other ideas that are not without controversy, including the building of new land, also known as land reclamation. Logan International Airport in Boston is built on land that was formerly wetlands. Overall, a general trend is toward living more densely.