Since 9/11, the NYPD has transformed itself into a mini CIA in an effort to fight terrorism. Associated press reporters Matt Apuzzo and Adam Goldman have admirably exposed the NYPD's intrusive, and possibly unconstitutional, secret surveillance program in a series of articles that won them the Pulitzer Prize. Their new book, Enemies Within, details how NYPD basically treats the entire Muslim population of New York City as potential terrorists—mass-surveilling mosques, deploying undercover "rakers" to snoop on random hookah bars, restaurants and cafes—with negligible results and less oversight even than the NSA's spying programs. To promote the book and refute the NYPD's pushback, the duo today released a cache of documents related to their investigations.

Apuzzo and Goldman will be joining us at 2 p.m. to answer your questions. Just ask in the comments using your Kinja account, or create a burner to ask questions anonymously.

Following is the prologue to Enemies Within.

Aurora, Colorado

Sunday, September 6, 2009

The bomber handled the chemicals carefully, just as they’d taught him. No need to rush anything and blow off his hand, or worse. A few years earlier, a curious college student in Texas had tried the same thing in his kitchen. A 911 dispatcher listened to him die howling, begging for help as flames engulfed his body.

Mix hydrogen peroxide and acetone, and nothing happens. The chemicals swirl around next to each other. In the presence of acid, though, they form the basis for a powerful explosion. The bomber’s acid of choice was muriatic acid, which he bought at a Lowe’s. Muriatic acid is used to treat swimming pools and clean concrete. But when it’s poured slowly into a mixture of hydrogen peroxide and acetone, clumps of white crystals appear. It looks like sugar, but it is as explosive as it is unstable.

The bomber used the Homestead Studio Suites kitchenette as his lab. He’d tried working in his aunt’s garage, but when she saw all the chemicals, she and her husband got suspicious and made him pour them down the drain. Nobody would bother him here. Unable to pay their rent, many residents had recently been kicked out of their apartments. Cats slept in windows. Children played in the parking lot alongside cars packed with furniture and clothes.

Forty dollars cash for a night in room 207. The bedspread was rough, and only the whir of the refrigerator drowned out the pulse of the highway. But he was not there to rest. He chose the motel because of its kitchen. It was a simple setup: builder-grade cabinets, a dingy white laminate countertop, and, most importantly, a stainless-steel, two-burner electric stove.

He had everything he needed. For weeks he’d been visiting beauty supply stores, filling his carts with hydrogen peroxide and nail polish remover. At the Beauty Supply Warehouse, among the rows of wigs, braids, and extensions, the manager knew him as Jerry. He said his girlfriend owned hair salons. There was no reason to doubt him.

On pharmacy shelves, in the little brown plastic bottles, hydrogen peroxide is a disinfectant, a sting-free way to clean scrapes. Beauty salons use a more concentrated version to bleach hair or activate hair dyes. At even higher concentrations, it burns the skin. It is not flammable on its own, but when it reacts with other chemicals, it quickly releases oxygen, creating an environment ripe for explosions. At its highest concentrations, hydrogen peroxide can be rocket fuel. Even with a cheap stove, it’s easy to simmer water out of hydrogen peroxide, leaving behind something more potent. It takes time, and he had plenty of that.

He added the muriatic acid and watched as the chemicals crystallized. The crystals are known as triacetone triperoxide, or TATP. A spark, electrical current, even a bit of friction can set off an explosion. If there’s too much acid, or the balance of acetone and hydrogen peroxide isn’t quite right, the reaction will speed out of control and trigger a chemical blast.

This was the moment when things often went wrong in basement laboratories, but he had done this before. A year earlier, he made his first batch under the watchful eye of his mentor. Then, a week ago, he made a practice sample in this same hotel. He took the finished product to an out-of-the-way spot, ignited it with a strand of Christmas tree lights and a battery, and watched it explode.

The white crystal compound had been popular among Palestinian terrorists. It was cheap and powerful, but its instability earned it the nickname “Mother of Satan.” Once, an amateur bomb maker in the Mojave Desert had walked under a stretch of power lines. The electrical charge in the air was enough to detonate his TATP blasting caps and send paramedics rushing to his aid. Now most professional terrorists preferred to use it in only the smallest of quantities as the detonator for a bigger bomb. Even the average suicide bomber didn’t want to carry around large amounts.

The volatile reaction was precisely the reason that all but the tiniest, containers of liquids were banned on airplanes. A terrorist who boarded with a large shampoo bottle full of the right chemicals could conceivably create TATP in midair. It was unlikely, but the US government concluded that it was too risky to chance. One tablespoon of crystals was enough to blow through a cinder block. One cup could rip open the hull of an airplane.

The young bomber wanted to cook up two pounds.

When he was done mixing, he rinsed the crystals with baking soda and water to make his creation more stable. He placed the finished product in a wide-rimmed glass jar about the size of a coffee tin and inspected his work. There would be enough for three detonators. Three detonators inside three backpacks filled with a flammable mixture and ball bearings—the same type of weapon that left 52 dead in London in 2005.

There was more work to be done. He had to finish the main charge, a mixture of flour and cooking oil. Concealed in a backpack and ignited by the TATP, these household ingredients would create a massive dust explosion and fireball. That could come later. The hardest part was complete.

He was ready for New York.

If you're in New York and would like to catch Apuzzo and Goldman in real life, they'll be appearing tonight at 7:00pm at Book Court (163 Court Street, Brooklyn, NY 11201) and tomorrow at 7:00pm at Bookmark Shoppe (8415 3rd Avenue, Brooklyn, NY 11209).