Won't keep us safe against Islamic terrorists. You need informants who will finger the terrorists before they open fire. Terrorists have to live somewhere, they have to eat somewhere, they have to travel, they have to communicate. Someone sees this. The landlady at the apartment, the counter person at the greasy spoon, the car rental clerk, the cell phone salesman. If you could talk to that someone, you could arrest the terrorist before he strikes. We need undercover cops to develop contacts inside the terrorist neighbor hoods, inside the mosques, anywhere we think terrorists might be.
We also need laws that allow us to imprison terrorists BEFORE they have done anything bad. Right now the criminal justice troops only work on crimes that have been committed. No commission, no action. Innocent until proven guilty.