Why does Obama get such an easy ride?

The Barack Obama love-in continues: in the Guardian Michael Tomasky describes him as a "less unifying enemy" than Clinton for the Republicans; and Jonathan Freedland describes him as the candidate who can appeal "beyond the party and win over the unconverted". Over at The Times William Rees-Mogg is musing on whether Obama is "the next JFK", comments on his "youth, idealism and style" and says he "could have a message for us all". Con Couglan in The Telegraph says his slogan "Change We Can Believe In" has "touched a nerve among ordinary Americans". Also at the Telegraph Liz Hunt describes Michelle Obama as a "formidable asset" and commends her for standing up to "attack dog Bill" who "played dirty" on race. Gavis Esler in The Daily Mail - the Mail, for God's sake - cannot contain himself: "talent", "charisma", "sets American hearts beating", "extraordinary life story", "electable, articulate, funny, educated and young", and so on. Very little if anthing about Tony Rezko (now behind bars after his bail has been revoked) or that house. If Obama does get the Democratic nomination my bet is that we will hear an awful lot more about this between now and November. Obama's "Tony who?" strategy works for now, but will not withstand the Republican attack machine. For God's sake, Rezko is a propery shark in Chicago (a city with certain traditions). Why does Obama get such an easy ride? His constant harping on "change" without telling us particularly what it is he wants to change from and to is open to derision, but it gets none. My theory is this: liberal criticism is stayed by political correctness, conservative criticism by brute calculation vis-a-vis November.