"[Blago] finally made good on a promise. He put President Barack Obama right in the middle of [Blago's] own political corruption case. And now it's finally clear why, from the moment of [Blago's] arrest in December 2008, White House spinners loudly portrayed our former Gov. Dead meat as some drooling, raving lunatic. ... But raving lunatics care little for their own survival. And in an amazing defense motion filed Thursday, [Blago] proved once again that he is quite sane. ... Obama's former patron and real estate fairy, the convicted influence peddler Tony Rezko, is a key player in the government's case. [Blago's] aim is to undercut what Rezko has told investigators. ... It is no secret that some in journalism get offended when anyone dares mention that the president was involved in Chicago politics. But the filing is not only a legal document, it's a political message from [Blago] to Obama. So allow me to translate the Chicago Way. 'Dear Barack, my old friend. I want you to use all your powers, all your skills, to make me an offer I can't refuse. I'm Mr. Celebrity-get-me-out-of-here, and you better get me out of here. Thanks, Rod.' ... US District Judge James Zagel surely isn't happy", John Kass at the Chicago Tribune, 23 April 2010, link: http://www.chicagotribune.com/news/columnists/ct-met-kass-friday-20100423,0,983180.column.
Obama can voluntarily appear and potentially look bad. Or he can resist appearing and look worse. Apparently, Obama chose the latter course.