When an American says “that’s history,” we usually mean that it’s not important anymore. And when we call something “ancient history” we mean that it’s irrelevant.

But that was definitely not the spirit of the meeting I attended at Portland’s East End School a couple of weeks ago, where the subject was putting much of the Munjoy Hill neighborhood into a historic preservation zone.

If the zone is adopted, owners of property that is considered to contribute to the neighborhood’s historic character would have to get a special permit if they wanted to change the exterior of the building.  To preservationists, these buildings and these streets are a historical record, like an archive of old letters and journals, that tells us and the people who will come later how we used to live. To some property owners, the zone is a promise that the appearance of the neighborhood won’t change even if the ownership of neighboring properties changes hands.

I live on the “Hill,”  but my block is not in the proposed zone, so I am officially agnostic. But fussing about replacement windows and hardscaping doesn’t fit with my understanding of Portland’s history.

Munjoy Hill was an undeveloped area until the Great Fire of 1866, when a tent city emerged to house burned-out refugees. Gradually, houses replaced the tents, many of them modest ones built for workers employed in the rail yards and sea port at the foot of Fore Street. The neighborhood was the home of Portland’s black community and the first stop for waves of immigrants, Irish, Italian and Jewish, who were looking for a better life.

But when people say they want to preserve the “historic character” of Munjoy Hill, they don’t mean that they want to make a place for refugees, workers and immigrants of all colors and religions. They mean they want you to get a permit before you pop some dormers in your roofline.

I prefer looking at old buildings than most new ones, too, but I worry that this focus on exteriors will discourage development in a city that desperately needs more housing. I would rather see more families with kids walking to work and school, even if the buildings that they live in are not as beautiful as the Victorians down the street. I worry that this desire to preserve the neighborhood will change the neighborhood.

But, zone or no zone, I’m also willing to admit that I can’t predict what’s going to happen next. I am confident, however, that a future Portland will be as different from the present city as the Portland of 1900 is from what we have now. And it will be shaped by forces beyond our control.

Climate change will not respect zoning. By the end of this century, sea level is estimated to rise between one and six feet, assuming that we take action to reduce carbon emissions. If we don’t, the people of Portland in 2100 could see water levels that are six to ten meters higher than today. If there are any fishermen left, they won’t have to worry about Commercial Street traffic because the cars will be underwater.

A warming planet is already making many places around the world uninhabitable. That is going to drive global migration that will shape a northern city like Portland much as European wars, famines and oppression did in the 19th century.

About 25 years ago, I went to a number of meetings in Portland where the public was told that the key to the city’s future prosperity was a world-class aquarium. It would turn Portland into a tourist destination and that would be a catalyst for a new era in economic development.

At none of those meetings did I hear anyone say, “You know what this town needs? About 200 restaurants, really expensive ones – and noisy!” And nobody said, “My cousin makes his own beer in the garage, and it’s better than what you can buy in the store. Maybe that’s the way to go!”

No one said it, but here we are. We are still aquarium-free, but all those restaurants and breweries did make us a tourist destination.

A history like that should make us humble about what we think is really within our control.