Last month, prior to the latest and biggest environmental summit in Johannesburg, U.N. Secretary General Kofi Annan stated that his first wish for the United States was that it would adopt the Kyoto Protocol on global warming. Apparently he did not know that the individual states are well on their way to doing that.

California law requires the State Air Resources Board to achieve the maximum feasible reduction in carbon dioxide from passenger cars. By far, the largest determinant of vehicle emissions is weight: Heavy cars and trucks take more gas to run. It seems impossible, under California law, to not eliminate both the SUV and the Buick Roadmaster.

Oregon law limits carbon dioxide emissions from all new power plants. That is certain to create great green consternation, as Oregon is largely run by hydropower. By economically discouraging virtually any new fossil fuel plant, we’ll just dam up a few more rivers, no? Don’t think so. The result will be more expensive power in the Pacific Northwest.

Massachusetts has put a hard cap on the amount of carbon dioxide that can be produced by power plants. However, utilities can get around that by “sequestering” carbon dioxide elsewhere, which means “planting trees.” One little problem, though. About all of Massachusetts that isn’t urban is already a continuous forest.

New Hampshire has also capped carbon dioxide emission, allowing power producers to “trade” emissions by buying and selling their “rights” to emit at the capped levels. My economist friends tell me this is the most efficient form of regulation. In this case, the word “taxation” can be substituted for “regulation” because that’s what it is. The utilities have the right (indeed the mandate) to pass the costs of these transactions directly to their users, i.e. you and me.

Legislation currently active and viable in New York would do exactly as the Kyoto Protocol says, reducing statewide emissions to 7 percent below 1990 levels.

Together, those five states tote up nearly 25 percent of the U.S. population.

Then there’s Hawaii, Idaho, Illinois, Louisiana, Maine, Maryland, Michigan, Minnesota, Nebraska, New Jersey, Oklahoma, Pennsylvania, Vermont, Wisconsin and Washington. All have seen global warming legislation in the last year, many of the bills are currently active, and most of the remainder will be resubmitted in their next sessions. We’re now up to half of the country.

In all, 56 separate bills to either limit carbon dioxide or to inventory it with the ultimate goal of limitation (otherwise, why bother to count it?) hit the state house floors last year. There’s certain to be more next year.

Meanwhile, six states are developing registries for carbon dioxide without legislative direction. “Registry” is a nice way of saying that we know exactly how much fuel your small business uses, how many miles you drive your cars, and a whole host of other things we’re sure to keep “in confidence.” Forty-one states either have or are in the process of emissions “inventories,” 23 have greenhouse gas “action plans” outside the legislative realm, and 12 have electricity portfolios directing power plants to produce a certain amount of energy from “renewable” sources. That last item always amuses the scientists in the crowd because there is no such thing as renewable energy. You use it, you lose it.

Secretary Annan should quit his crabbing. He’s gotten his way. But in each and every case of enacted legislation, inconvenient physical and economic limitations are likely to get in the way, from lack of proper technology to increased energy prices that are liable to be unpopular.

Nor would much warming be prevented because while legislation and talk are cheap, they can’t trump physics. The entire Kyoto Protocol, if adopted worldwide, wouldn’t change global temperature enough to even be measured in the average lifetime of everyone on earth today. Instead, if you want to have a significant affect on the earth’s temperature, you have to somehow legislate people to reduce their total energy use by about 50 percent in the next 50 years, even as the number of people using energy will nearly double in that time. That works out to about 25 percent of today’s energy running tomorrow’s house, car and economy.

That’s not going to happen, despite the wishes of Annan or virtually every state. Legislation can devolve from the United Nations to the United States to individual states — but physics is eternal.