on the other hand, though, if you -- and they won't -- but if you take the statements of dzhokhar tsarnaev at face value, this was a plan his brother dreamed up and brought him into just a couple of months ago, that, you know, the instructions match what you would have found in al qaeda's online inspire magazine. if you follow the instructions to a tee and you went out into the woods in massachusetts and you set off a smaller version of the bomb to see if your bomb recipe and your initiator worked, and you did it again, you could pretty much go back and make that happen. and that is not that far-fetched. the al qaeda instructions and inspire magazine, whether it's for a fuse detonation or a remote detonation, is meant to be bomb making for dummies. it's meant to keep it simple. >> pretty terrifying if that's what happened. stay with me. when we come back, i want to talk to you more about all this. plus joining us is paul wolfowitz on what appears to be a huge intelligence break down and more on what authorities knew about the suspects' mother