this is bad. really bad.
not that the constitutional committee was making much progress (at least that's my impression from reading second or third accounts of the deliberations from where i am, 7500 miles away), but this will probably make things even worse. it's about a month before the deadline to finish the new iraqi constitution and to put it to a referendum. they've been negotiating for months and the drafting committee hasn't yet agreed on some of the most basic issues. at least they had gotten beyond who would be on the committee. but these killings are just going to open the issue right up again.
on top of that, it has removed some of the few sunni politicians who were willing to cooperate with the shi'a-sunni dominated government. plus, it will probably serve to intimidate any other sunnis who were considering stepping up to the plate.
adding this all together means it is going to be a lot harder for to end up with a viable constitution in the near future, never mind next month's deadline.