My view is somewhere in between "This is the best we could expect" and "We're saved!".
Firstly, this is the best we could expect. I want to re-emphasize the fact that there is no way that COP21 would have resulted in a legally binding treaty.
John Kerry made this clear to the delegates:
The one word that almost sank the climate talks - POLITICO
That means the word change could have obliged the Obama administration to submit the final deal to the Senate for its approval. And inevitably, the GOP-led chamber would kill it on sight. "When I looked at that, I said, 'We cannot do this and we will not do this,'" Secretary of State John Kerry told reporters afterward. "'And either it changes or President Obama and the United States will not be able to support this agreement.'”
In fact, not even 24 hours after the agreement was adopted, the Republicans already have brought out the axes and knives:
Obama optimism over climate pact tempered by GOP opposition - Yahoo News
Senate Majority Leader Mitch McConnell of Kentucky said Obama is "making promises he can't keep" and should remember that the agreement "is subject to being shredded in 13 months." McConnell noted that the presidential election is next year and the agreement could be reversed if the GOP wins the White House.
This is not an empty threat. If the Republicans win the White House next year and keep control of both house of the U.S. Congress, there is no doubt in anyone's mind that they will shred up the Paris Agreement, abolish the Clean Power Plan, undo probably every pro-climate initiative that the WH put in place in the past 8 years and probably even bring back the Keystone XL pipeline and probably also pass their own laws for agressive "drill baby drill" style pro-fossil fuel initiatives. This is not unexpected.
But let's say that does happen and we play out the worst case scenario here. The other 195 countries that adopted the Paris Agreement will still probably march forward with it. Europe definitely, China probably and India more than likely. From the tea leaves I've read, it seems like India has seen the light and know that they only benefit from clean energy and would suffer unnecessarily if they stuck with coal. China doesn't have much of a choice, they are already suffocating in their own smog, so they will reduce emissions for that reason if no other. Europe doesn't have climate change deniers like we do, and is generally pro-environment across the board. The Paris talks took place in Paris for a reason.
So, even if the worse case scenario plays out, I am still confident the world will generally march away from fossil fuels. We are also forgetting the important market signal being given here. If you are heavy into fossil fuels, are you buying on Monday or selling? Maybe just holding, but many investors will now be a little more skittish when investing in fossil fuels. And likewise, investments in clean energy just became that much more attractive. That's great news for TSLA and SCTY by the way, as well as pretty much every other clean energy company.
So, while a good future is not guaranteed, a guaranteed good future needed the Paris Agreement, and it now has it.