The environment will continue to deteriorate as long as capitalism continues to be the modern world's economic engine. 

This is according to Gus Speth, dean of the Yale School of Forestry & Environmental Studies, writing in his new book, The Bridge at the Edge of the World: Capitalism, the Environment, and Crossing from Crisis to Sustainability.
Seeing an "emerging environmental tragedy of unprecedented proportions," Speth says the book's aim is to describe a non-socialist alternative to capitalism. That alternative includes moving to a post-growth society and environmentally honest prices, curbing consumerism with a new ethic of sufficiency, rolling back corporate control of American political life, and addressing the enormous economic insecurity of the average person.
"My point of departure is the momentous environmental challenge we face," Speth says. "But today's environmental reality is linked powerfully with other realities, including growing social inequality and neglect and the erosion of democratic governance and popular control." Speth examines how these seemingly separate areas of public concern are intertwined and calls upon citizens to mobilize spiritual and political resources for transformative change on all three fronts.
Speth argues that aggregate economic growth is no longer improving the lives of most Americans and suggests that in some ways it is making individuals worse off-environmentally, socially and psychologically. 
"It is said that growth is good – so good that it is worth all the costs, that somehow we'll be better off," says Speth, "We are substituting economic growth and more consumption for dealing with the real issues-for doing things that would truly make us better off."
The book calls for measures that provide for universal health care and alleviate the devastating effects of mental illness. Speth points suggests we guarantee good, well-paying jobs and increase employee satisfaction, minimise layoffs and job insecurity and provide for adequate retirement incomes; introduce more family-friendly policies at work, including flextime and easy access to quality child care; and provide individuals with more leisure time for connecting with their families, communities and nature.
Speth writes that Gross Domestic Product (GDP), the dollar value of all goods and services produced by the economy, is a poor gauge of human well-being or welfare. The book cites studies showing that throughout the entire period following World War II, as incomes skyrocketed in the US and other advanced economies, reported life satisfaction and happiness levels stagnated or even declined slightly.
He says that these studies suggest the need for a radical rethinking and reordering of society's priorities. Obsession with consumption and GDP growth has now causes more harm-to the environment, social fabric and world security-than good.
It took all of history, Speth notes, to build the $7-trillion world economy of 1950; today, economic activity grows by that amount every decade. At current rates of growth, the world economy will double in size in less than two decades. "Society is facing the possibility of an enormous increase in environmental deterioration, just when we need to move strongly in the opposite direction."