I don't think such pictures should be illegal, but I really think they hurt rather than help the cause. I think the same is true, BTW, of some of PETA's "shock" ads. Attempting to make someone uncomfortable is more apt to make them dislike you than anyone else.
These photographs are the most accurate image of abortion available. Those who fear the revelation of the truth usually have something to hide.
In a sense they are the most "accurate" image, but in another sense they miss the essential point. I think it's much better and more effective to focus on the positives of life. Things like the picture of the fetus grasping at the doctor's finger after he performed surgery on it.
Trying to illustrate abortion by showing pictures of blood and gore is like trying to illustrate the Taliban's destruction of Buddhist statuary by showing pictures of the rubble. Far more effective to show what once existed and does no longer.
I am not hoping to make anyone dislike anyone else. I simply want people to have the right to show this atrocity for what it is. I agree that it is beneficial to show the positive option, but I also feel that it is necessary to show the consequences of the negative option. This is a two sided issue and focusing on one side of the argument at the exclusion of the other prevents a conclusive result.
For instance, let's pretend it's 1943 and I am in Germany protesting the state sponsored internment and murder of people of Jewish ancestry. It would be good for me to portray the positive potential these people could have if they were free, educated, and respected with full human dignity. This, however, is insufficient. It is also necessary to show the horrific repercussions that result from their subjugation for people to be able to make an informed judgment. If you are ever ever in Washington D.C., visit the Holocaust Memorial and you may develop a better understanding of this distinction.