Former Marine, FBI agent and Islamic terrorism expert John Guandolo has argued very cogently that Obama's nominee to head the CIA, John Brennan, was unsuited for the job given his willful blindness to, or frank denial of Islamic jihadism in virtually all its manifestations.  Guandolo, as part of his case against the Brennan nomination also put forth (here, here, here, and here,) the plausible hypothesis that Brennan, succumbing to an influence campaign by Saudi intelligence, converted to Islam while serving the US in Saudi Arabia. Although Guandolo has repeatedly made plain that the more dangerous aspect of Brennan's reported conversion is that it occurred as part of an overall influence operation by Saudi intelligence, the vitriolic responses to Guandolo's allegations have focused exclusively on Brennan's alleged conversion.   

Interviewed by US News, Ibrahim Hooper, himself an American convert to Islam, and communications director of the Council on American Islamic Relations (CAIR), the Hamas-linked, unindicted co-conspirator in the Holy Land Foundation jihad terrorism funding trial, clarified that although he  had "no knowledge of Brennan converting to Islam," if the allegations were true, Brennan had merely "reverted" to the primordial faith of Islam:

Everyone is born in a state of Islam and your parents make you into something else-Jewish, Christian," he said. The conversion process itself, Hooper noted, is uttering a short profession of faith, the Shahada. "From that moment on you're a Muslim," said Hooper, "of course it helps if you believe it."

Shocking as Hooper's claim may sound to non-Muslims, he is simply re-stating with candor classic, mainstream Islamic doctrine, consistent with Koran 3:65, 3:66, 3:67 and the mainstream exegeses of these verses, for example,  from the seminal Tafsir al-Jalalayn, meaning "The Commentary of the Two Jalals," named after its two Egyptian authors: Al-Suyuti (1445-1505), a brilliant multidisciplinary scholar; and his mentor Jalalu'd-Din al-Mahalli (1389-1459). The great contemporary Dutch Islamologist Johannes J.G. Jansen notes in his treatise "The Interpretation of the Koran in Modern Egypt," Tafsir al-Jalalayn remains one of the most popular as well as the most authoritative Koranic commentaries in Egypt. Here are the glosses on Koran 3:65, 3:66, 3:67, from  Tafsir al-Jalalayn:

When the Jews claimed that Abraham was Jewish and that they were following his religion, and the Christians made a similar claim, the following was revealed: O People of the Scripture! Why do you argue about, dispute over, Abraham?, claiming that he belonged to one of your [two] religions, when the Torah was not revealed, neither the Gospel, but, a very long time, after him, and it was only after these two were revealed that Jewry and Christianity came into being. What, do you not comprehend?, the falsehood of what you say?... Lo! (h膩, 'lo', is for calling attention to something), You (antum, 'you', is the subject) are those (the predicate is [what follows]) who dispute about what you know, concerning the affair of Moses and Jesus, and your claim to be adhering to their religions: why do you then dispute concerning that of which you have no knowledge?, of Abraham's circumstances; and God knows, his circumstances, and you know not... God, in order to dissociate Abraham [from their claims], said: No; Abraham in truth was not a Jew, neither a Christian, but he was a Muslim, professing the Oneness of God, and a han墨f, who inclined away from all other religions towards the upright one; and he was never of the idolaters.

Shamim A. Siddiqi, an influential American Muslim commentator and author (for  example, of Methodology of Dawah Ilallah in American Perspective, or as Daniel Pipes notes "The Need to Convert Americans to Islam"), in  a candid late 2001 letter,  ostensibly rebutting allegations of Islamic supremacism within the American Muslim community, opened by  proclaiming the "innocence" of Sheikh Omar Abdel Rahman ("who is suffering a life sentence for no wrongdoing of his own but because of the Jewish lobby's prejudices against Islam and Muslims"), despite Rahman's conviction for the 1993 World Trade Center bombing, and other planned acts of terrorism in the New York Metropolitan area. Siddiqui's letter included a re-affirmation of Ibrahim Hooper's mainstream, supremacist viewpoint that Islam was the primordial "Abrahamic" faith:

Abraham, Moses, Jesus, and Muhammad were all prophets of Islam. Islam is the common heritage of the Judeo-Christian-Muslim community of America, and establishing the Kingdom of God is the joint responsibility of all three Abrahamic faiths. Islam was the din (faith, way of life) of both Jews and Christians, who later lost it through human innovations. Now the Muslims want to remind their Jewish and Christian brothers and sisters of their original din [religion]. These are the facts of history.

A decade ago, theologian and Islamic scholar Mark Durie highlighted the dangers of such mainstream, traditionalist Islamic doctrine-a toxic dogma that combines historical and religious negationism, while, under the guise of "affirming" Christianity and Judaism , seeks to replace them altogether within a universal, Sharia-based Islamic order.

What is being affirmed is in fact neither Christianity nor Judaism, but Jesus as a prophet of Islam, Moses as a Muslim etc. This is intended to lead to 'reversion' of Christians and Jews to Islam, which is what Siddiqi refers to when he speaks of 'the joint responsibility' of Jews and Christians to establish 'the Kingdom of God'. By this he means that American Christians and Jews should work to establish shari'ah law and the rule of Islam in the United States.

Siddiqui articulated that goal unabashedly in his 1989 Methodology of Dawah:

Every Muslim living in the West will stand in the witness box in the mightiest court of Allah...and give evidence that he fulfilled his responsibility as witness against the people; that he left tone unturned to bring the message of the Qur'an to every nook and corner of the country where he used to live...

It matters little for the Islamic Movement as to whether it takes one or many decades to make the ideology of Islam prevail over the mental horizon of the American people. The action must be taken now. The Movement must be set out forthwith. The struggle for making Allah's Deen dominant must take shape without any further lapse of time...

The Muslims of America (both immigrants and indigenous), individually as well as collectively have been ordained by Allah to fulfill that obligation. They are to carry out the message of Prophet Muhammad and establish Allah's Deen. It is incumbent upon us without any excuse...

The Muslims of America have no option. They have to carry out the struggle in the way I have discussed in this book to the last breath of their lives until either the mission is accomplished or they pass on from this world as Mujahidin-fi-Sabil-Allah.[i.e., Holy warriors, jihadists, fighting to impose Sharia, emphasis added]

This is the overall context in which John Brennan's  words and actions ((here, here, here, and here) must be considered before he is confirmed as our next CIA Director.