Actually the market based solution consumes both time and mony, now time is sth that we dnt have, at all.
We need a mass greenification, and we need it soon, before low lying countries like Bangladesh simply drown.
Yes. But imposing regulations on people and businesses will mean that they oppose the government. And in a country like Bangladesh, the government will never take any step which may cause them to lose votes... Few governments will be prepared to risk this actually.
Furthermore, if a regulation is imposed, the effect on the economy and businesses is almost immediate. Worker strikes and economic recessions could occur..
In addition, no one country can be completely blamed for CO2 emissions. All countries contribute, more or less. A market based "cap and trade" system like that in the Kyoto protocol will help all countries and businesses to participate, with quotas allocated. Whereas, regulations are often on a local basis and not all governments in the world will agree to put strict pollution control regulations on their citizens like Bangladesh and other developing countries.
Furthermore, if a regulation is imposed, like no polluting plastic factories, the existing factories who will update to the latest less polluting technologies (assuming they're able to pay for that, or receives subsidy), will have no further incentive to think or invest in R&D for greener technologies. Whereas in a market based system, if you have a less polluting technology, you'll be charged less. Thus, there is a clear incentive.