I'm not trying to be snide or anything, but why does it matter if two bombing victims were unwittingly carrying the bombs? They're still just as dead as the other people. I'm also not sure why it matters if they were mentally disabled or not, as if that makes it worse than when a normal person dies. I'm worried that people have gotten so desensitized to this stuff that they only notice unusual bombings, and so the death of two gains more attention than the death of one hundred.
And this should serve as a reminder of how inherently stupid racial profiling is. When people can be carrying bombs that they're not even aware of, it really is best if the terrorists don't know who will get through security more easily. Telling people about your security provisions doesn't seem like a very good idea, especially not when you're tipping them off on how to get around them.
Perhaps some day soon we'll have political leaders who have better solutions to fighting terrorism than war and tighter security.