By Seth Johnson

The disclosure that guns purchased in the federal Bureau of Alcohol, Tobacco and Firearms' Fast and Furious anti-drug cartel program have been found at a crime scene in the United States did not surprise Dan Bongino, a former Secret Service agent who raised the very scenario last year.

Bongino wrote in his New York Times bestseller, "Life Inside the Bubble," that, "One of these weapons is going to be tied to a crime on United States soil. It's only a matter of time."

Confirmation came in the form of documents obtained by Judicial Watch in a lawsuit against the Phoenix police department. They revealed an AK-47 rifle purchased by federal agents during Operation Fast and Furious was used in a gang assault in Phoenix last year.

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Deputy Attorney General James Cole, the No. 2 official at Justice, announced his resignation shortly after news broke linking the Phoenix gun to Fast and Furious.

He explained he wanted to pursue work in the private sector.

Attorney General Eric Holder previously announced his resignation Sept. 25, the same day a federal judge ordered the Justice Department to detail every document it withheld from Judicial Watch in a separate lawsuit involving Fast and Furious.

Operation Fast and Furious gained national attention when a gun purchased by agents was used in the December 2010 murder of Border Patrol Agent Brian Terry. His team was ambushed after corralling five illegal immigrants who had just crossed the border. Most of the media attention focused on crime involving the guns in Mexico, despite Terry being murdered on U.S. soil.

"The media missed the real scandal. The guns are being used here, not just in Mexico, and the real scandal is the cover-up that the administration engaged in," Bongino said.

Bongino believes that many of the agents involved had good intentions, but they were mismanaged by a Justice Department bureaucracy and a U.S. attorney's office that refused to publicly own up to what happened.

"Everything in this administration is political," Bongino said. "They did not want a photo of a dead American child with a Fast and Furious gun next to them."

Read "Life Inside the Bubble" and find out just what it's like behind the barricades, the tape and the closed doors.

The Justice Department under Holder has not cooperated with congressional investigators looking into the operation. Holder was also voted into civil and criminal contempt of Congress after refusing to comply with a subpoena from Rep. Darrell Issa, R-Calif.

In his book, Bongino puts the blame squarely on the Justice Department and the federal law enforcement culture that requires setting an appointment to schedule an arrest and discourages any prosecution that has even the slightest chance of ending in a loss for the government.

"By nature, a probable cause arrest is unpredictable, and unpredictability is the enemy of our federal justice system. The fastest way to get on the bad side of the U.S. attorney's office is to start making PC arrests late at night without having thoroughly exhausted all investigative avenues," Bongino wrote.

By January 2010, the agents had identified 20 suspects who had paid over $300,000 for 650 guns, according to Forbes, which should have been enough to make arrests and close the case.

Acting as a "straw purchaser" of weapons is illegal, and many of the buyers did not have the financial assets to make such expensive purchases on their own. Even after a straw buyer working with ATF agents delivered guns to a trafficker and recorded the exchange on a wiretap, arrests were still not made.

Until Brian Terry was murdered nine months later.

Within 24 hours of Terry's murder, one prime suspect was arrested, and 19 other suspects were indicted two weeks later. Bongino says the behavior of the U.S. attorney's office reeked of ineptitude and arrogance.

"They were moved to action only when they realized that there would be severe political ramifications after the highly publicized death of Agent Terry and from the investigation that would follow," Bongino wrote. "Their laziness and lack of integrity had real-world consequences, and despite the numerous warnings from the ATF agents on the ground who were sounding the alarms, the DOJ acted only when there was a political cost to pay."

Bongino said he hopes the revelation about an AK-47 used by a gang in Phoenix is the last time Americans have to read a story about Fast and Furious guns being used in the U.S., but he fears that such preventable bloodshed will continue.

Hear Bongino:

Order "Life Inside the Bubble" and find out just what it's like behind the barricades, the tape and the closed doors.