BLACK TOM EXPLOSION.JPG

Police investigate an explosion on Black Tom Island in Jersey City on July 30, 1916.

(AP File Photo)

Dark Invasion: 1915, Germany's Secret War and the Hunt for the First Terrorist Cell in America

Howard Blum

Harper, 474 pp., $27.99

Reviewed by Tom Deignan

They had launched a secret war against the United States, and now they were ready to execute their most destructive plot yet. The mission’s code name? "Jersey."

The notorious explosion on Jersey City’s Black Tom Island on July 30, 1916, caused millions of dollars in damage, led to at least five deaths and forced Americans to rethink their desire to stay out of World War I.

But according to Howard Blum’s fast-paced and timely "Dark Invasion," Black Tom was also the culmination of an elaborate German campaign of sabotage that might have been far more deadly if not for a heroic, largely forgotten New York City detective named Tom Tunney, whom Blum and others have called "the first head of Homeland Security."

Aside from blowing up dozens of ships carrying munitions and other supplies, this yearlong campaign of terror also included an attempt on the life of financier J.P. Morgan Jr. (whose companies made valuable loans to German enemies) and the detonation of a bomb at the U.S. Capitol building. "No one had been killed," Blum writes, "but a message had been delivered: America was under siege."

And while much of the book’s terrorist scheming and detective work is done in Manhattan, the German saboteurs also used a wide range of Jersey locales for their plotting and execution. Prior to the Black Tom explosion, four Jersey City laborers were killed in an explosion at the Detwiller and Street munitions factory. A Dupont powder mill in Pompton Lakes was also targeted.

Hoboken, meanwhile, was a hive of pro-German sentiment, according to Blum. The city was often called Little Bremen (after the north German city), and shadowy figures such as former German military officer Walter T. Scheele, president of the New Jersey Agricultural Chemical Company, set up elaborate labs there to manufacture explosives.

Dynamite purchased from a Perth Amboy store also plays a key role in Tunney’s investigation, as does a chase through the streets of Weehawken, which Blum re-creates with all the drama and suspense of a Hitchcock film.

The anti-American sabotage operation began not long after the start of World War I. German officials wanted to make sure the U.S. stayed on the sidelines and believed the best way to do that was to keep law enforcement officials busy and hamper supply shipments to Britain and France. Much effort was put into making the explosions seem accidental, though by July 1915, when a "pro-German fanatic" (as the New York Tribune called him) was implicated in both the Capitol bombing and Morgan assassination, it was clear to many who was behind this mayhem.

Indeed, with his understandable emphasis on the cloak-and-dagger operations, Blum still could have spent more time analyzing why President Woodrow Wilson and the American public were willing to endure these deadly attacks for more than a year. Especially after the notorious sinking of the Lusitania in May 1915, which killed more than 120 Americans. Similarly, some readers might want to know more about how the bombings affected, or were debated within, the larger German-American community.

Either way, the task facing Blum’s hero, Detective Tunney, was to stop the bombings with his tiny NYPD bomb squad, whose previous operations against Italian anarchists included dressing up undercover cops as washerwomen to thwart a bombing of St. Patrick’s Cathedral. Blum deftly illustrates how ill-prepared the U.S. was to deal with such international conspiracies, leaving Tunney to develop innovative tactics ranging from phone-tapping to Donnie Brasco-style infiltration.

Most ominously, the Germans eventually launched a campaign of germ warfare on U.S. soil, though Tunney’s work ultimately managed to discourage the increasingly skittish Germans. Tunney, "without at the time realizing the effectiveness of his actions or the lives he’d saved, had won a great victory," Blum writes.

Blum’s story is, at times, riveting, and his publishers are proud to note that Bradley Cooper’s production company has purchased the rights to "Dark Invasion," with the Oscar nominee currently slated to play the trailblazing detective. No less interesting is the book’s supporting cast, whose lives remained fascinating even after World War I.

Blum doesn’t mention this, but consider the aforementioned New Jersey chemist, Scheele, who was ultimately indicted for assisting the Germans, then fled for Cuba. In the fall of 1920, when almost 40 people were killed by a bomb in Manhattan’s Financial District, whom did government investigators ask to analyze the explosives? None other than Scheele, who’d returned from Cuba and turned informer.

Sounds like there might be another Bradley Cooper movie in there.

Tom Deignan, a writer and teacher who lives in Woodbridge, is a regular contributor to The Star-Ledger. Share your thoughts at nj.com/opinion.

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