By R. James Woolsey and Peter Vincent Pry 

ISIS has captivated Western attention for so long with its gruesome beheadings, stabbings, vehicular homicides, shootings and bombings in Europe and the United States, the horrific aftermaths deservedly the focus of television news, that virtually forgotten is the world’s biggest terror threat — Iran’s IRGC, the Islamic Revolutionary Guard Corps.

The IRGC, often misidentified in Western press as the Iranian Revolutionary Guard Corps, Iran’s Islamic Revolutionary Guard Corps dwarfs ISIS by any measure.

ISIS never had more than about 30,000 fighters, equipped mostly with small arms, with very little access to high-tech weaponry.

In contrast, the IRGC has about 125,000 fighters. It is the only terror organization in the world with an army, navy, and special forces.

The IRGC Army has 100,000 troops in 20 infantry divisions. The IRGC Navy has 20,000 sailors, including 5,000 Marines. IRGC Special Forces, called the “Quds” (“Jersusalem”) Force numbers 5,000.

The Islamic Revolutionary Guard Corps also has reservists called the Basij Militia, paramilitary volunteers numbering 90,000 normally — but potentially capable of mobilizing an estimated 300,000 to 1 million fighters.

The IRGC is not to be confused with Iran’s regular armed forces, called the Artesh. Iran’s regular army, like normal armies everywhere, is responsible for defending Iran’s territorial integrity and political independence.

The Islamic Revolutionary Guards Corps is the instrument by which Iran is the world’s leading sponsor of international terrorism — including against its own people.

The IRGC was founded on May 5, 1979, in the immediate aftermath of Iran’s Islamic Revolution that overthrew the shah and brought to power the mullahs, the Islamic clerics who run Iran today. The mullahs purged the regular army, but still did not trust it.

So they formed the Islamic Revolutionary Guard Corps as a military and ideological counterweight to the regular army and to the people, to ensure that there would be no counter-revolution to overthrow Iran’s Islamic state. The IRGC’s purpose is to preserve Iran’s Islamic nature, to stop “deviant movements” among the people that the mullahs see as a threat to Islam, to serve as “morality police” enforcing the tenets of Islam upon national life.

The IRGC’s purpose is also to advance the Islamic Revolution in the Middle East and the world.

The genesis of the IRGC and its purpose parallels that of Adolph Hitler’s establishment of the Schutzstaffel (the SS) as a check on Germany’s regular army, the Wehrmacht, to ensure the permanence of Nazi power, to enforce ideological purity among the people, and to serve as the elite “tip of the spear” in Nazi Germany’s conquest of the world.

The IRGC has killed and wounded thousands of Americans, far more than ISIS, in Iraq and Afghanistan. The IRGC has killed more U.S. allies too through their terror operations. For example, Hezbollah and Hamas, the twin terror plagues of Israel, are subsidized by the Islamic Revolutionary Guard Corps.

While ISIS has sometimes been described as the first terrorist state because of their occupation of lands in Syria and Iraq — from which ISIS is now on the verge of being expelled — many analysts believe the IRGC is the dominant power in Iran, even more powerful than the mullahs.

The Islamic Revolutionary Guard Corps is deeply woven into the political and economic fabric of Iran. Former President Mamoud Ahmadinejad was an IRGC member, as are many of Iran’s parliamentarians and mayors.

The IRGC is a multi-billion dollar business empire, controlling much of Iran’s economy.

For example, Iran’s biggest construction company, Khatam al-Anbia, worth $7 billion, with 25,000 engineers and staff, belongs to the IRGC. The IRGC also controls the Telecommunications Company of Iran, worth $7.8 billion. Iran’s wealthiest charities, including the Mustazafan Foundation (Foundation of the Oppressed) and the Foundation of Martyrs and Veterans, belong to the IRGC.

Most worrisome about the Islamic Revolutionary Guard Corps is that it is in charge of Iran’s missile forces and nuclear, chemical, and biological weapon programs.

The U.S. Institute of Peace notes that, “Iran has the largest and most diverse ballistic missile arsenal in the Middle East.” And that most Iranian missiles “were acquired from foreign sources — notably North Korea.”

Iran and North Korea are strategic partners, pledged by treaty to share science and technology. North Korean scientists are in Iran helping their space program, which is controlled by the IRGC.

According to the U.S. Institute of Peace: “The Islamic Republic is the only country to develop a 2,000-km missile without first having a nuclear weapons capability.”

A Congressional Research Service report “Iran’s Foreign and Defense Policies” (October 2016) and the Federation of American Scientists warn of evidence that Iran is pursuing chemical and biological weapons in violation of its obligations under the Chemical Weapons Convention and Biological Weapons Convention. German Federal intelligence warned in 2015 the Islamic Revolutionary Guard Corps sought German equipment “for atomic, biological, and chemical weapons in a war.”

When the smoke clears over Raqqa and ISIS is no more in Syria and Iraq, the IRGC will be there, and its proxies will be everywhere, casting a darker, more ominous shadow of terror over the world.

• R. James Woolsey was director of the Central Intelligence Agency. Peter Vincent Pry is chief of staff of the congressional EMP Commission and served in the House Armed Services Committee and the CIA.