George Tiller gets killed by a murderer. It happens that Tiller was also an abortion doctor who focused on children just before birth. Late-term abortions -- very controversial even among the most ardent of pro-choice believers -- are what Tiller did best.
President Obama recognized that this will given him an added edge promoting his own prochoice beliefs through the press. While he no doubt realizes the murder is wrong on every level, this will help him look on the ball regarding his Supreme Court choice. Strangely helpful timing.