The Islamic State (ISIS) is a gang of thugs who glory in their sadism, videoing their beheadings of their captives, taunting gays with tweets of #LoveWins accompanying photos of their executions of gays, and boasting of their plans to bring about imminent mass murder and destruction inside the United States.

The Islamic Republic of Iran, on the other hand, is a major player in Middle Eastern and global politics, courted by the Obama administration and the recipient of its largesse as sanctions have been lifted.

Yet as I show in my new book The Complete Infidel’s Guide to Iran, although ISIS is the object of the world’s scorn and horror and Iran is accorded respect and accommodation, in numerous important ways, Iran is worse, and a more significant global threat, than ISIS.

  1. Iran has a nuclear program. The Islamic State would love to get its hands on nuclear material and construct a bomb. By contrast, due to Barack Obama’s disastrous deal with the Islamic Republic, Iran is well on its way to doing so. Even if it abides by all the terms of the nuclear agreement, within ten years, all restraints on its activity will have expired, and it will be free to construct as many nuclear bombs it can afford (and can pay for with the billions Obama has given to Iran in sanctions relief). Given Iranian officials’ oft-repeated boasts that Israel will soon be destroyed, and that the United States will be as well, this prospect is truly chilling.
  1. Iran funds and controls a global network of jihad terror organizations. While the Islamic State’s claim to constitute the restored caliphate – the sole government to which Muslims owe allegiance, according to Sunni Muslim theology – has won it the allegiance of tens of thousands of Muslims (and several existing jihad terror groups) worldwide, Iran already has that to which the Islamic State aspires: a network of jihad terror organizations with a truly global reach, ready to do Iran’s bidding up to and including the killing of its perceived enemies.

This network’s foremost member is Hizballah, which is active not only in Lebanon but in South America’s Triple Frontier region, as well as in Mexico, where there is evidence that it has trained and collaborated with drug cartels. Other members include the Sunni jihad groups Hamas and Palestinian Islamic Jihad, as well as the Houthis in Yemen and the Iraqi Shi’ite group Kata’ib Hizballah.

Iran doesn’t work only through jihad terror groups. It has funded the Spanish left-wing populist party, Podemos, and in July 2012, Hamid Mohammadi, the Iranian cultural affairs counselor at the Iranian Embassy in Ottawa, Ontario, Canada, gave an extraordinarily revealing Farsi-language interview intimating that Iranians in Canada had “preserved their strong attachments and bonds to their homeland” and should strive to “occupy high-level key positions” so that they could “be of service to our beloved Iran.” Mohammadi’s words sparked an investigation of espionage and subversion in the Iranian embassy in Ottawa that ultimately led to its being shut down.

  1. Iran’s Shi’ite eschatology could make it not just willing, but eager to use nuclear weapons. Shi’ite Iran awaits the return to earth of the Twelfth Imam, the mythical savior figure who will conquer and Islamize the world. One of his predecessors, the sixth Imam, Jafar Sadiq, once prophesied that the Imam Mahdi, or Twelfth Imam, would come at a time when the Shi’ites were experiencing persecution to a terrible, unprecedented degree – indeed, he would not return until, said Jafar, “two-thirds [of the] population of the world is not destroyed.” Presumably, then, the Twelfth Imam will return when one-third of the world’s population has been destroyed.

 Former Iranian President Ali Akbar Hashemi Rafsanjani, who remains influential in the Iranian government, boasted in December 2001 that a nuclear bomb “would not leave any thing [sic] in Israel but the same thing would just produce damages in the Muslim world.” It could also, with millions of Muslim dead, move the Twelfth Imam to return, to put a stop to this unprecedented persecution of the Muslims.

This could mean that the Iranians might want to nuke Israel in order to draw retaliatory nukes that would induce the return of the Twelfth Imam – and no concessions from Obama or his successor would dissuade them.

  1. Iran was involved in 9/11. The Islamic State has inspired Muslims in the U.S. to kill Americans, but so has Iran, with a much more macabre record of success than ISIS has yet amassed. Although its involvement in the 9/11 jihad plot has received very little notice, it was so unmistakable that in 2010, a federal judge determined that Iran, Hizballah, the Islamic Revolutionary Guard Corps, the Iranian Ministry of Intelligence and Security, and other Iranian government departments, as well as the Ayatollah Khamenei himself and former Iranian president Ali Akbar Hashemi Rafsanjani were all directly implicated in Iranian efforts to aid al-Qaeda in its 9/11 plot.

That puts the blood of nearly 3,000 Americans on the Iranian mullahs’ hands. And if the mullahs get their way, they will be following up that carnage with many more like it.

Robert Spencer is the director of Jihad Watch and author of the New York Times bestsellers The Politically Incorrect Guide to Islam (and the Crusades) and The Truth About Muhammad. His latest book is The Complete Infidel’s Guide to Iran. Follow him on Twitter here. Like him on Facebook here.