London terrorist had twice been referred to police over his extremist views

Let's continue to ignore the fact that these ISLAMIC TERRORISTS pose a threat to all that they consider infidels. How's that working out for you?

They are excellent investigators, not so hot in regards to prevention. They need better psychological profiles to select high potential terrorists from thousands of suspects. Nearly every terrorist attack has been telegraphed in some form or another.

I don't think this is a total failure of the system. I appears the system works but there is something or someone that is not allowing the system to work. Look at the budget of the US Intel agencies. Its in the Billions. Even with that, one example here, the Russians communicated (colluded for you Liberals) with the Obama Admin about the Tsarnov Brothers and their ties to Dagestan and for some unknown reason they were allowed to carry out their operation. I think something else is going on here on a big picture scale. Why else would elected officials sit idly by and watch the people they represent get slaughtered in daylight by a group that has openly pledged their death to kill infidels???