As I write this, US President Barack Obama has just taken off for Paris and the UN Climate summit. I beat him here - after all he doesn't have to go through customs or anything so he travels faster than I do.
This is a very big deal to Obama. Getting an overarching worldwide agreement on climate change has been a central theme of his administration since he took office.
Remember the talk of calming seas when he became the Democratic nominee? Small problem - he's not going to keep that promise.
A recent study by the Massachusetts Institute of Technology found that if all of the countries live up to their pledges to reduce greenhouse gases, the Earth will still warm 3.5 degrees Celsius by 2100.
Without any action, the planet is expected to warm by 4.5C.
These scientists say the combined actions will in essence reduce the temperature by 1C.
That will not stave off the worst consequences of climate change. It's also an open question as to whether the countries will live up to their commitments.
The Obama administration has been working hard to avoid this agreement being called a treaty. If it is a treaty, he would have to get two-thirds of the US Senate to agree to the terms.
He wouldn't be able to make that happen.
The senate is run by Republicans and if you look at polls nearly seven in 10 (68 percent) of Republican voters believe the threats posed by climate change are greatly exaggerated.
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Without the endorsement of the Senate, any agreement can simply be changed or ignored by the next president who takes over in 2017.
If a Republican is elected, you can all but guarantee the changes ordered by Obama won't even be recycled, they will just be thrown in the trash.
The majority of Republican presidential candidates say they don't believe in global warming. The ones that say that it is probably true add, however, that they wouldn't hurt the US economy to address it.
A senior White House aide has told me that they plan to have aspects of a final agreement that are legally binding. They won't give details as to what that might look like.
But in reality, very few things in the US can stick without the Congressional seal of approval. The president has gone it alone on cutting greenhouse gases, issuing executive orders and telling the states to figure out a way to make it happen.
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That is by no means a done deal. Dozens of states are fighting the order in court.
In the end, it might be the Supreme Court that decides if the president has the power to single-handedly impose strict guidelines.
The White House argues this is a good start. They are counting on massive investments from governments and the private sector to jump start technological innovations that will make green energy the smart choice.
They point to the significance of the world standing together and saying climate change is real and needs to be dealt with.
Obama will be able to say he helped push the world to this point but he won't be able to say he lived up to his goal.
It was a big promise he made back in 2008, saying: "This was the moment when the rise of the oceans began to slow and our planet began to heal."
The oceans will continue to rise, as for the healing power, that will be in the hands of the next US president.
Source: Al Jazeera