Make Earth Day Every Day.” While we might not always live up to this ideal, I try to keep this quote from Denis Hayes, founder of the Earth Day Network and president of Seattle’s Bullitt Foundation, in mind when I need a little extra motivation to be a better environmentalist: “Listen up, you couch potatoes: each recycled beer can saves enough electricity to run a television for three hours.

It is already too late to avoid mass starvation.

Environmentally, business in America in 1970 was very similar to business in China today. Even if a CEO wanted to be a responsible corporate citizen, he (and they were all "he's" then) simply couldn't invest a billion dollars in pollution controls to produce a product that was indistinguishable from those of his competitors. His products would be priced out of the market. Passing laws that created a clean, level playing field for whole industries had to be a core focus of the 1970s.

Earth Day gathered up those strands, and dozens more, and knitted them together in the public consciousness as "environmental" issues. The nation was pretty startled when 20 million people hit the streets. Congress, which had adjourned for the day to go back to its districts, was blown away.

These are not exhortations from overwrought extremists, but carefully phrased warnings from some of the world's finest scientists.

Politicians had always viewed environmental issues as narrow things of no great political consequence. Sort of NIMBY issues. A big part of the reason was that the groups that cared about wilderness didn't talk with the groups that were trying to stop freeways from cutting through inner cities, and neither of them talked to the folks who wanted to stop the military from dumping Agent Orange on Vietnam.

We need a firm cap on carbon emissions from fossil fuels. No coal, oil, or gas could enter the economy until the buyer had a permit. All permits would be auctioned by the federal government, and the number of permits auctioned would be decreased by three percent per year. Permits could be traded, but they could not be created out of whole cloth by companies that plant forests or dump iron filings at sea.