It's probably good that the NYPD is telling the public that they were able to buys parts to build a 1.3 ton truck bomb two years ago, because then it raises the awareness of how these parts are too accessible. But check out this excerpt from the NY Times:
The detectives, who had no formal training in the use of explosives, used information gathered over the Internet and from easily available books to educate themselves about what to buy, the police said. They traveled to an agricultural supplier in upstate New York and another in Pennsylvania to buy the ammonium nitrate, and they went as far as they could in building the bomb by loading it into a white plastic water tank that they placed in the back of a rented van similar to the vehicle used in the World Trade Center bombing in 1993.
The entire plan took four months to carry out and cost $7,000, including $700 for the ammonium nitrate, $170 a month to rent the Bronx storage space, $731 to rent the van and $813 for a 360-gallon tank.
We're surprised there wasn't a diagram and addresses for where you could get these materials, too! The NY Post says, "Key components were intentionally left out to minimize danger" - but it was still detonated out in the Bronx " just to prove that it could have been deadly."
The issue on the table is that the ingredients are too readily available. The 2,450 pounds of ammonium nitrate, which is a fertilizer, was bought when the detectives said they just got an apple orchard, and Deputy Commissioner James Falkenrath said in a Congressional meeting, "Why are these companies sending ammonium nitrate to Brooklyn?" Uh, there are a lot of brownstone neighborhoods to gentrify with new plantings? [The fertilizer distributor did contact the ATF, who was then told it was an NYPD undercover op, but the NYPD's point is that there are still no significant barriers, like security checks, to purchasing them upfront.]