Fact is our intelligence organizations stop dozens of attacks a year. Some are bound to get through. Instead of second guessing try supporting them. These guys have a really tough job to do. They pick of bits and pieces of information from all over the world and have to try to figure out what's going on. There's hundred of various terrorist organizations they're monitoring, each of which is working on multiple plots. Our intel guys have to match the info with the group and the plot and try to figure out who wants to make what go boom, how and when. To understand intel analysis do this: buy 100 puzzles, make sure they are all the same type of scenes but different scenes, make sure they're all at least 500 pieces, now take a fist full of pieces out of each box throw them on the floor, burn the boxes and all the remaining pieces, now take that pile of random fist fulls and tell me what each puzzle is a picture of. That's what these guys get to work with, random bits of information where step one is figuring out which "picture" it goes to, then what the picture means, and they have brutal deadlines.
We should be thanking these guys, we should thank them for their miraculous success rate. It's truly amazing how many of these things they stop.
Considering that the CIA already had a written outline of the attack, acquired when Ramsi Yussef and his partner were arrested, and already had under suspicion some of the bin Laden people involved, you would wonder why they didn't round up the "usual suspects" and sweat something out of them as to what was going to happen.
Do the Mossad and French intelligence have to come over here themselves and round up and question the known members of the bin Laden organization for us?