1) The economics of every process must take into account the cost of the environment. If it's not going to biodegrade, that costs. If it comes from an unsustainable logging practice, that costs. If came in a boat from across the world, that costs. Adding the cost of environmental consequences to all stages of production opens up the room for investors to sensibly bet on less damaging production methods. We will look back at this time and rub our eyes when we realise what an insane free-for-all it has been.
2) A global body needs to be created to handle environmental policy, probably balancing quality of life with environmental outcomes. This body should be elected, but independent from politicians. Just like monetary policy was been removed from the easily bendable hands of politicians, the environment needs to be too. This deals with i) the short term thinking required of politicians [elections] ii) the global nature of the problem.