Over the years muawiyah, we have come to expect you not to see the point. If you can't see that there is no difference between Zaqawi and Sadar, then all the posts in the world will do nothing more than allow you to continue to nit pick until the points are entirely lost and you have hijacked yet another thread.
With Sadr in the employ of Iran's government, and Al Zarkawi doing the bidding of AlQaida interests, I would suggest they do not have identical political ambitions or standing. If this involved European people I am sure you could discern some level of difference.