In North America, the prevailing attitude is that recycling and composting of organics is the greenest way to go. An anti-incinerator website claims:
According to the U.S. EPA, “waste to energy” incinerators and landfills contribute far higher levels of greenhouse gas emissions and overall energy throughout their lifecycles than source reduction, reuse and recycling of the same materials. Incineration also drives a climate changing cycle of new resources pulled out of the earth, processed in factories, shipped around the world, and then wasted in incinerators and landfills.
Unfortunately, almost nobody is doing enough recycling and composting; most of North American garbage is still being landfilled. in Copenhagen they are not shipping garbage all over the country. They are keeping it close at hand, within the city itself, and they are not landfilling anything.