Given the constraints of an extremist opposition, there’s probably not much more Obama could have done on climate change. He sums up his achievements and the need to move forward in an article in Science, written by him, although almost certainly not actually written by him. This is the first time a sitting president has ever published in the prestigious journal.
Of course one can argue that Obama’s biggest weakness is thinking that anyone cares what is published in a journal like Science instead of playing the dirty politics that actually leads to power in this country. It would be nice if this country could have nice things, but what a pipe dream.