An ambitious political agreement re Climate Change would probably be better than a less ambitious legally binding one, the latter would be "policed quite effectively by world public opinion". I fully agree with this point of view, as expressed by Graham Watson, Member of European Parliament (Liberal Democrats, ALDE) in "Graham Reports from Copenhagen;
Update Monday 4th December PM". in his blog www.grahamwatsonmep.org
Inter alia, Mr. Watson writes:
"...This must be the first time world public opinion has mobilised so effectively, putting pressure on the government leaders to act ....
... Will the commitments be legally binding? It may be better if they are not, since in that case they will be less ambitious. A political agreement would probably be policed quite effectively by world public opinion."
I believe that Mr. Watson's rationale is right on the mark.