The last I checked I was an atheist, so I'm not sure how I'm pushing a Christian narrative. Furthermore, you mean my anti-Shia narrative, since nothing I've indicated so far has anything to do with Sunni's, seeing as Iran is a Shia nation. If anything, my claims lend credence to Sunni victimhood, but while I am very sympathetic to the Sunnis caught between ISIL on one side and scared of a Shia government in the other, I think Sunni Wahhabism has much to answer for.
But the difference in current geopolitics is that KSA is more fearful of, and has more to lose from ISIL than any other middle eastern country while Iran greatly benefits from the spread of their religious extremism. ISIL would greatly like to supplant KSA as the keeper of Mecca, Medina, and the Qabaa, while extremist Shia groups look to the Ayatollah as their spiritual leader. Can you see the distinction there?
Furthermore, I think your assertions overstate the actual history. Nixons alliance with the Saudis didn't ease any fears of sectarianism, but again the Saudi theocratic rentier government has been trying to tamp down on extremism since their legitimacy was threatened in 1979. The deposing of the Shah wasn't intended to stoke religious extremism, but it did and that is our legacy. The Neocons flirted with fomenting sectarian violence against the USSR in supporting the mujahideen, especially with logistical support and surface-to-air missiles. The Bush administration helped Iran inadvertently through beaurucratic incompetence and replacing a secular leader with a Shia dominated government who informally looks to Iran as its ally. But you also have to acknowledge that the removal of a secular dictator in favor of a Shia government has done more to balance the scales of power in favor of the Shia and lessened the power of our Saudi (Sunni) allies. This has a net effect of leveling the playing field between the two sides - while increasing the paranoia of Sunnis, it also gives the Iranians greater leverage in the region (giving them a greater stick in which to force Saudi cooperation). The Obama administration has flirted in small scales with supporting Syrian Sunni fighters and has prolonged the conflict by refusing to negotiate with Assad. The US has played an outsized role in the Middle East and must answer for it.
But again, these pale in comparison to the level of _sustained_ investment the Iranian government has made over the past 30+ years. We're not talking about a series of one-off realpolitik maneuvers. Iran is universally recognized as the most skilled operator in the region for good reason - no other country has operated in these areas for as long, or understands the culture or motivations as well. No other country is coordinating bombings in South America, and no other is trying to cultivate fundamentalist extremism there.
Lastly, I'd duspute the idea that I'm biased against Iran. I think the Persian people are probably the most amenable to western values out of any in the region, and current geopolitics notwithstanding they are probably the best hope for America to secure a long term peace in the region. I hope the moderate factions continue to achieve more successes as they have done with the nuclear accords, and there may even be a chance to end the heartbreaking tragedy in Syria by acknowledging their regional influence.
But I feel compelled to tell the truth as I see it, and to me that is acknowledging the fact that Iran is currently the worlds leading cultivator of fundamentalist terror. That doesn't mean I conflate the Ayatollah with the Persian people, that means the government of Iran is the central coordinator of Shia extremism throughout the world today, their spiritual leader. As with any government there are factions, but Irans hardliners came to power in the revolution and maintain power to this day. If moderates succeed in gaining more ground the region will be much safer overall.
Lastly, you again dodged my point. America is not cultivating Christian terror groups that look to Obama as their spiritual leader.