In architecture the terms sustainable and green are used to signify a design or construction method implemented for the betterment of the environment. (At least these terms started off being used for that purpose, and not for the marketing effort that seems to be more prevalent today.) These terms form the perception of designers and builders being more ecologically responsible. But true sustainability is a balance between energy in and energy out. If you consume more of the environment than can be replenished (both naturally and artificially) then the balance is off.
So architecturally speaking, can a building be considered sustainable if the environment around the building is not considered sustainable? Is a building green if everything serving the building (such as the roads, utilities, artificial landscape) is really not all that green? If every single building in the Phoenix metropolitan area was LEED Platinum and the metro area still had the suburban sprawl that it has today, would Phoenix become the quintessential sustainable city?
In Green Metropolis, David Owen makes the argument that the keys to sustainability are living smaller, living closer, and driving less. His arguments coincide with the Reduce part of the sustainability mantra of Reduce, Reuse, Recycle.
Reduce your living quarters. Reduce the amount of area in your home you need to fill with your stuff, and clean, and maintain, and pay taxes on. Reduce the amount of volume in your home you need to heat and cool. Reduce the amount of lawn you need to water, spread fertilizer on, and mow.
Reduce your separation from the places you need and want to go. Reduce the number of places you can frequent without always having to drive your car. Reduce your risk of becoming obese and contracting diabetes, heart disease, liver disease, respiratory disease, and a score of other ailments. Reduce the number of excuses for not getting enough exercise (walking to go somewhere rather than walking for the sake of walking). Reduce the area that public services (police, fire, power, sewer, trash) need to cover.
Reduce your dependence on the automobile. Reduce the amount of miles you put on your car, thus reducing the amount of maintenance, gas, and other services done to your car. Reduce the amount of money you pay on car insurance (typically based on the number of miles you drive in a given year). Reduce your dependence on the cost of gas. Reduce the amount and size of roads needing to be built, and reduce the amount of maintenance required for these roads. Reduce the amount of traffic for the people who still require a car to get around.
The big idea that Green Metropolis is pushing is having communities designed for people rather than for automobiles. Of course there are still people in New York City that still have to drive. Public transportation and walking will not work for every single person. But wouldn’t you like the choice of being able to choose a method for getting somewhere?
Almost all of the cities and towns of North America are designed as a car monopoly. If you want to go anywhere you typically have the only choice of driving your car. Imagine if the only way to buy food was going to McDonald’s, and the only way you could get on the internet was through America Online. I’m not against the car. In fact, I love driving. I just like having a choice.
Blue Architecture 
I think the “Reduce” part of the Green Movement has been underemphasized because it so viscerally clashes with our definition of what it means to be American. In America, you can have it all, you can own it all, and you can have it anywhere and as much as you want. The past several years’ experience of war, tragedy, and economic slowdown might not be enough to make people reconsider this cultural self-definition, but perhaps it’s a start. The most recent issue of Utne describes this sort of problem–if America has defined itself as a culture of consumers, and we suddenly cannot or should not consume as much as we used to, with what do we replace that consumerism (which is not to be confused with capitalism itself)?
The article’s author suggests some kind of community-focused involvement, which he calls “communitarianism”, and on transcendental (or some kind of spiritual) involvement. Many religions, philosophies, and cultures have some kind of non-grasping or non-greed rule–that is, don’t take more than you need. In that way, “Reduce” is just reminding people that green living isn’t just using less packaging, it’s buying less stuff in general. Less food and less gasoline can ultimately equal less impact on the environment overall.
Capitalistic societies have overcome major shifts in the status quo of operating. How is the economy going to be affected when we no longer have slaves? How are people going to find jobs when machines can do the work of a hundred men? What is going to happen to all of the people who lost their jobs to a computer? And our current major shift, what type of job market will prevail that is aligned with our need for environmental stewardship?
I’ve always felt that living in a democratic society didn’t mean that you could do whatever you wanted (the definition of anarchy), but rather that all citizens were responsible for their actions. We as Americans need to become more responsible for what we do, which means a better understanding of how we live affects everything around (other people, the environment, society in general). It will require a shift in how we live in a consumer lifestyle, although I have to argue that the term “communitarianism” is probably the wrong word to use as a guide for a better society. (Too close to “communism”, which is a word Americans have been taught to fear since the early 1900s. Maybe we should use the word “Patriotification” to replace consumerism, that way if you’re against it you can be ridiculed.)
My theory on why “Reduce” isn’t celebrated as much a green strategy – too simple and it’s just not that sexy. “We’ve replaced all of our incandescent bulbs with fluorescent bulbs” – green sexy. “We’ve decided to save electricity by not turning on any lights” – you’re a moron that lives in the cromagnon times.
My favorite point is reducing our dependability on our automobiles. I try to drive a lot less these days, and instead use my bike, or even take the bus.