Let's talk about the evidence as seen on TV.
One of the pressure cookers has a serial number that is legible. That can be tracked.
They can track all cell phone pings at the precise moment of detonation.
I think they are going to catch the assholes.
I hope so. If I recall correctly, it was the serial number found on the axle of the van that was blown up in the World Trade Center that led to the arrest of those apes.
Let's see....ah, yes! I remembered correctly!
https://en.wikipedia.org/wiki/1993_World_Trade_Center_bombing
In the days after the bombing, investigators surveyed the damage and looked for clues. While combing through the rubble in the underground parking area, a bomb technician located some internal component fragments from the vehicle that delivered the bomb. A vehicle identification number (VIN), found on a piece from an axle, gave investigators crucial information that led them to a Ryder truck rental outlet in Jersey City. Investigators determined that the vehicle had been rented by Mohammad Salameh, one of Yousef's co-conspirators.[21] Salameh had reported the van stolen, and when he returned on March 4, 1993, to get his deposit back, authorities arrested him.[22]