The carbon emissions of industry that generates energy for society illustrates the much larger issue of externalities. Externalities are the waste and by-products of corporations, and they are not legally obliged to factor these into the cost of production of their goods or services. The cost of these externalities are offset to the community, because in theory, the community should have the resources to deal with the externality. Of course this was before we had corporations with economies the size of countries. Externalities can be anything from the toxic chemicals dumped into a river, the destruction of ecosystems, human rights violations from the abuse of cheap labor in third world countries, nuclear waste and of course carbon emissions from coal fired power plants.
Not factoring these externalities into the cost of producing a good or service reduces the cost. This reduction in cost forces the board of a company to take the lowest cost route available because, by law, the corporation is legally obliged to maximise the financial returns to the shareholder. Even if a board of a corporation agrees that it's is an undesirable course of action, morally wrong or clearly unsustainable environmentally, this fatal flaw in the design of a corporations legal structure prevents even the most environmentally aware directors doing what is right by the earth and ultimatley the human race.
Carbon trading is an attempt to put a cost on the energy industries externality (carbon emissions) so that a cost can be factored into energy production that burns coal. This very focused approach allows the issue of changing the law to force corporations to deal with their externalities, to be avoided. I'm not saying not to apply carbon trading, but this is the very layering of regulation that business complains about. The real issue is how much longer can we continue to destroy the very ecosystem that allows the human race to exist all because we allow this glaringly obvious legal flaw to continue.