Most countries use taxes to further social goals as well as as for raising revenue. The U.S., for example, is debating raising the gas tax to reduce the use of petroleum-based fuels.

Almost 42 Billion-with-a-B petroleum-based plastic bags were used in grocery stores, Wally Worlds, and all the other stores worldwide in January, 2008. Most go to landfills as waste or to roadsides as litter. Plastic bags are not biodegradable. They remain where they land pretty much forever.

Ireland took agressive action in 2002 when that country passed a tax on plastic bags; Irish consumers now pay 33 cents per bag at the cash register.

Six years into the bag tax, most smart, progressive people in Ireland carry cloth bags. Sales of plastic bags has dropped to nearly nothing there.

Ireland has moved on with the tax concept, proposing similar taxes on customers for A.T.M. receipts and chewing gum. Bedposts will be so lonely with no chewing gum to keep them company overnight.

So here is the real (and the environmentally most important) question: What kind of plastic bag does that “smart, progressive” person carry his or her trash to the dump in?