Because embracing anthropic climate change involves drastic controls on emissions, manufacturing, and energy generation (specifically coal) as well as being an excuse to raise a variety of taxes on an already strained economy.
The crazy thing is, if we weren't spending trillions on the force projection necessary to secure our unsustainable fossil based energy infrastructure, we could easily use that wealth to build a sustainable solar/nuclear-based infrastructure - no drastic controls or raised taxes required.
I don't believe there isn't a way to manage a peaceful transition. We went to the moon because we had the will to do it. We could do the same with our energy infrastructure.