When Syed Farook and Tashfeen Malik massacred 14 people in San Bernardino, California, last December, newly retired Department of Homeland Security agent Philip Haney discovered that a case he developed might have prevented the attack if it had not been shut down by his agency and Hillary Clinton's State Department.

Now, Haney tells WND that the mosque where Orlando killer Omar Mir Siddique Mateen worshiped several times a week also has a tie to that case.

He noted that the FBI twice had Mateen on its radar, but closed down the investigations both times.

Mateen opened fire early Sunday morning at a "gay" nightclub in Orlando, killing at least 50 people and wounding another 53 in what is being described as the deadliest mass shooting in U.S. history.

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DHS agent Philip Haney's blockbuster revelations of the federal government's appeasement of supremacist Islam are told in his new book "See Something Say Nothing"

As a member of one of the National Targeting Center's advanced units, Haney helped develop a case in 2011 on a worldwide Islamic movement known as Tablighi Jamaat, as he recounts in his new book “See Something, Say Nothing: A Homeland Security Officer Exposes the Government’s Submission to Jihad.” Within a few months, the case drew the “concern” of the State Department and the DHS’s Civil Rights and Civil Liberties Office because the Obama administration believed it unfairly singled out Muslims. The intelligence, however, had been used to connect members of the movement to several terrorist organizations and financing at the highest levels, including for Hamas and al-Qaida.

In the immediate aftermath of the Orlando massacre, Haney has found that the Islamic Center of Fort Pierce, Florida, is part of a network in the United States that originated in the Indian subcontinent.

The Fort Pierce mosque's website features a link that demonstrates its relationship to the Shariah Board of America, a division of the Rahmat-e-Alam Foundation, which operates the Darul Uloom Chicago madrassa.

The madrassa is closely affiliated with the Institute of Islamic Education, which was a major component of Haney's Tablighi Jamaat case.

Along with the State Department's and Department of Homeland Security's quashing of the case in June 2012, the administration subsequently ordered the deletion of an additional 67 records related to a report on the Institute of Islamic Education.

Haney explained that this kind of information comprises the "dots" that counter-terrorism analysts connect to form cases that are used to identify potential terrorist threats.

"This case struck me as very similar to the San Bernardino shooting case," Haney told WND on Sunday. "I suspected that they were both part of a national and international network of organizations."

He said that using open-source information, beginning with the Islamic Center of Fort Pierce, he discovered Sunday afternoon that his initial suspicions were correct.

"It's exactly how I would have approached a case if I was still active duty," he said.

"The FBI had opened cases twice on him, and yet they found no evidence to charge him," Haney pointed out.

"It means they didn't go through the same basic, analytical process that I went through over a three- or four-hour period in which I was able to link the mosque to my previous cases."

The Orlando Sentinel reported the FBI interviewed Mateen three times for having alleged terrorist ties. He came to the FBI's attention in 2013 after he made inflammatory remarks to co-workers, but the investigation was closed.

In 2014, he was interviewed again for making contact with a suicide bomber.

Another member of the Fort Pierce mosque, 22-year-old Moner Mohammad Abusalha, blew himself up in an attack in Syria in 2014 with an explosives-laden truck

Islamic law in America

Haney noted that the Shariah Board of America to which the Fort Pierce mosque is linked is one of a number of Islamic groups that issue fatwas, or decrees, instructing Muslims how to comply with Islamic law in the United States.

The fatwas of the Shariah Board and similar groups often address competing loyalties, such as whether American Muslims should join the U.S. military or work for the U.S. government.

He urges Americans to confront the reality that Shariah is not compatible with the U.S. Constitution.

He pointed out Article VI of the Constitution states the Constitution is the supreme law of the land.

“As long as we mislead ourselves with a false narrative about the threat we face, we’re never going to come to the place where we can develop a counter-strategy to it," he said.

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