Either it (the blasphemy) was responsible for all of the deaths or none. I believe it was the latter. I cannot see how it could have been responsible for any deaths unless the cartoonist has mastered the art of pictorial mind-control. The individuals who physically caused the deaths are responsible. 'Provocation' is no defense, particularly when one is being provoked by a cartoon. Also, where are you getting 'racist provocation' from. Islam is not a race. It is a religion that is followed globally and across all races.
We did have a rather lengthy discussion of the Danish cartoons case some pages back. My argument was that the cartoons were more racist than blasphemous. Islamic people, particularly Arab Muslims, may very well think of themselves as a race/ethnicity, in the same that Jews talk of the 'Jewish race'.
My understanding is that the cartoonist was very familiar with the Islamic world/culture/sensibilities and the cartoons were calculated to offend and provoke a reaction (remember that the Koran forbids visual depictions of Allah/Muhammad). He should have been able to foresee what might happen in response to the publication of the drawings.
The problem is that as new people join the discussion the same issues keep reappearing and past points have to be restated. We all take a central stance on these issues, then look for different ways to explain or justify our position. It's difficult to not end up sounding repetitive. Sorry.