Global Warming: The cost of deciding what action to take.

With all of the controversy concerning the human impact aspect of global warming we might want to keep this in mind:
1. We have been releasing materials proven to be greenhouse gasses into the atmosphere for over 100 years.
2. The Earth is right now in a warming trend.
If there is no connection between the two (doubtful) and we take action, we stand only to improve and upgrade our methods of energy production. If we are indeed the cause of this warming trend (likely) and we do nothing, we will be dooming humanity to drought and famine. If we act on limiting greenhouse gas emissions, we can't lose. If we do nothing, we are gambling with the future of the human race