Instead of a binding treaty, he may be forced into patchwork solutions because Congress won't act.
One for all and all for one. Sacrifices would be shared equally.
But Congress looks to be breaking up that party.
Lawmakers are not expected to pass a climate-change bill anytime soon because of resistance from industry and consumers over the price tag of binding carbon targets. And a recession and the huge debate over healthcare have also sidetracked the issue.
This has forced President Obama into awkward diplomacy. He really can't commit to targets for reducing carbon emissions – as President Clinton did in signing the Kyoto treaty – without first having a climate-change law in place.
So difficult choices lie ahead. The concept of a new international treaty with binding targets may be defunct as long as the world's largest emitter of carbon emissions isn't on board.
One idea is for the US to go it alone or in concert with a few other countries and cut greenhouse gases at a pace that each country can endure. This would be discouraging news for those who say that the whole world, or at least the rich nations, must start reducing carbon emissions within a few years to avoid natural disasters later this century. The Copenhagen summit was supposed to be the "meeting that saved the world."