Iran's theoretical nukes threaten Israel

Iranian nuclear goals:

Iran wants theoretical nuclear capability in accordance with the nuclear non-proliferation treaty that gives them the right to be capable to develop nuclear weapons and strike back with such in case they or an ally face a nuclear first strike. Since Israel does have nuclear weapons, a full scale conventional attack by non-nuclear backed forces was pointless due to having zero chances of success against a last ditch Israeli nuclear first strike capability against anything from civilian to military targets. Iran develops a nuclear knowledge umbrella that serves as a minimum deterrence second strike capability. From underneath that umbrella Israel can again be threatened with full scale conventional wars they can possibly lose.
Other countries with theoretical nuclear capability are South Africa, that disarmed their nukes, or Italy and Germany, who participated in the now French nuclear weapon program (and were cheated from the having the result), or Brazil and Turkey that voluntary decided to cease their nuclear weapon efforts.
None of them proclaims their legal second strike right nor uses it as a political tool. This assumed Iranian mindset has to do with nuclear ambiguity, a policy of deterrence or "area denial" by minor powers who feel threatened by major powers. Apartheid South Africa was and North Korea(it's unknown whether they have more than then the tested nuclear device) and Israel(their official policy) are examples of this policy. Iran under the Shah was a staunch US ally with oilfields next to the Soviet Union and had a similar program as the Islamic Iranian Republic today. It was aimed at nuclear ambiguity in order to deter the Soviet Red Army that Iran could never have defeated in a conventional battle. It served as a recognizable status symbol, despite not equalling the nuclear partnership level with known deploy able bombs, but allowed for considerable indigenous efforts and pride at achieving something.
The Islamic Revolution brought Islam to the forefront and with Islam came ethics that make a first strike use of possible nukes impossible to justify. That's the major difference between the ongoing Iranian nuclear program since the days of the Shah.The next step was to drop any ongoing drive for a nuclear bomb altogether, according to the official CIA information on that issue. That's sensible, because it diverted scarce resources from other fields of widening nuclear knowledge. A theoretical nuclear power, like Japan, never committed to any research on nuclear explosions that are just maximized neutron flux in fission material within a short time frame amplified in energy emission by surrounding fusion material. Engineering the neutron flux is the bread and butter of running nuclear reactors. You can be capable of building some kind of nuclear bomb, not the most refined and efficient kind, without that much research. Explosive effects of all nuclear weapons pale in comparison to their nuclear fall out area. Mutually Assured Destruction is not about blowing each other to pieces ("duck and cover" works for some people), but salting the earth with radioactive poison.

The Iranian nuclear program's effects:
Iran is on the long list of countries that are "Soviet leftovers" and "need a new US-friendly government" "before the next challenging superpower rises". 9/11 served as an initial excuse for starting this whole series of operations that was knowable long before. Z. Brzeziński is one of the guys bragging about this "secret plan", just like he brags about his complicated Afghanistan trap for the Soviets, but this time prior to events and I don't think he's the mastermind on this one. Our media somehow fails to mention that we have all the time been moving from one country on the publicly known list to the next with another enticing pretext (former NATO SACEUR Wesley Clark neatly sums it up) during the Bush(ridiculed for "lack of intellect") and Obama(a Nobel peace prize recipient) presidencies. The nuclear story is just one such excuse, but much better than the Iraqi WMD or fighting al-Qaeda for over a decade in the Hindu Kush.

The nuclear research story helps Iran at the moment to foster an internal defensive alliance of the population, while at the same time giving them the option to go for a know-how threshold that could force Israel to acknowledge a different strategic environment. For Iranians there’s obvious information that seems verifiable and counter factual to the Iranian nuclear bomb project, like diminishing stocks of enriched material due to transfers to medical facilities in Tehran. This does help to widen the perceived injustice induced stabilization against intruding outsiders. The longer this story goes with high tension claims, the more boring it will become. Like every repeated story, it can reach an infinite threshold of boredom, while real-life effects due to sanctions remain obvious. After a long time of strong mutual support, dissension can grow in Iran due to perceived misuse of such a support by current leaders for other ends.That can cause a backlash of public opinion change proportional to the perceived moral support previously provided and the willingness to endure hardships for this stance.

Conquering Iran:

The current legal-nuclear-ambitions-derived-unfair-sanctions-story serves as a rallying point for Iranians to support their government and face these sanctions. They could do forever if they feel everyone is sharing equal in misery. The economic favours and influence displayed by Middle Eastern elites and mighty guardian institutions will run counter to meritocratic aspirations for chances of a boom of educated youths, even more so under duress that highlights existing inequality with scarcity. It’s not clear how long a narrative of being compelled under duress will carry on, but the ends of the Soviet Union and Warsaw Pact are showcases of narrative conviction failure. 
The Islamic Revolutionary Guard are the loyal supporters of the political system, who use that position in power for economic gains, not unlike Russian siloviks or Chinese princelings. This phenomena of power derived from a mixed clout of state and commercial enterprise control by a class of system servants is nothing new under the sun. It does not necessarily lead to any kind of public outrage. There are societies with historic roots and traditional procedures with mutual recognition for this very kind of system. Song-dynasty China is an example of the high industrial productivity and quality of life such a system can achieve. However, the reasons for the Song military defeats by the northern tribes, such as the Mongols, are an ongoing debate.
Iran has some real major political compensation option for achieving an envisioned level of nuclear proficiency. That entices them to continue down that road for as long as it takes to have their theoretical nuclear capability umbrella recognized. Going down this road is the best option to unify and quell dissent that made some headlines after the last Iranian presidential elections. It’s like giving viagra to an old man; he can become addicted to fulfilling his dreams and risks death due to his constitution being unable to cope with the other effects.

Iran will commit to their best option of violence for coercing invasive foreigners to accept the integrity of their current political system. They follow an ethic code of current Shia (sometimes mortal enemies of Sunni) interpretations of Islamic military jurisprudence that excludes nuclear first strikes. Pakistan is the non-hostile neighbouring Sunni non-secular Muslim country with nuclear weapons. They have no idea how these weapons fit with their Muslim ethics, but they give great status and satisfaction. If you deny Iran a convincing ability to fight a decisive military engagement to their liking, they will look for other options of defiance.

As long as Iran believes in their chance of defending their political system with their military hardware, they will be enthusiastic about following down that road. The more they believe, the better such a believe can be crushed without creating an attitude of defiance that makes occupation a more costly adventure than Afghanistan. War is a ritual as will be outlined below in another post.
It’s another masterpiece of the smokescreens used in such high level power games. Nevertheless, as the previous regime change shows, there are negligible chances of ending the Iranian nuclear program that has always been an integral part of Iranian ambitions. The realistic option is recognition of Iranian theoretical nuclear capability in exchange for not making it a dagger against Israel. That's similar to convincing Pakistan to abstain from using their nukes as a political lever in the Persian Gulf and beyond.
The Western public should, through the news exposure, recognize current Iranian governments as mad would-be-killers who want a bomb, because no sane person is that enamoured with nuclear reactors. This gives green light to any future measures necessary for regime change and is a case in point on how the Iranians can be convicted of thought crimes that are less hard to find than Iraqi WMD.

Regional politics:

The Sunni Gulf-States are against any Iranian power and prestige gains which could unhinge the current financial benefits for the ruling Sunni tribal nepotism from the oilfields that lie beneath the habitat of a majority population of subdued Shia tribes. Shia and Sunni are two Islamic interpretations that have been frequently at war since the foundation of that religion, with Iran being the major champion of Shia faith. Arab states have frequently been called "tribes with flags", highlighting the tribal hierarchy of power with top dog tribes getting more and better services, money and weapons than less government affiliated tribes that are the usual troubleshooters in rebellions. How should an economy work, other than with labour imports, if the best educated men are constantly obsessed with crushing the hopes of the least educated?
Real Arab nations are Tunisia (tracking themselves back to Carthage), Egypt (with millennia of nationhood) and Morocco (for centuries the kingdom/s of resistance against foreign Muslim domination and Christian conquest). Iran is predominantly not Arabian (their Shia-Arabs also live on their oil fields)  and somewhere in the middle between tribes and nations with an ethnically diverse landscape.

Israeli Sephardi speak all Arabic dialects as native languages and are an important piece of projecting power through knowledge for the US-SIGINT backed diplomacy. Without Israel, this capability to interfere with some level of understanding in major oil regions of the world would vanish. 

Looking closer at Israel:

It’s unlikely that within some decades any Near Eastern force could conventionally defeat the Israeli military and occupy their land, although an alliance of Iran, Iraq, Syria, de facto independent Hezbollah-land, Egypt and Hamas-land Gaza could theoretically launch a giant invasion that would be a tad more threatening than the last time, when Saudi Arabia participated instead of Iran. 
An improved ability of the ongoing harassing warfare with conventional forces can cause fatigue while Israeli influence in the Middle East can be curtailed by a viable counterweight through nuclear prestige that helps to bandwagon interests (all other nuclear ambitions were forcibly shut down or Americanized).Hezbollah is an Iranian sponsored borderline phenomenon between regular and irregular forces that follows this path of endemic violence.

Israeli demographics of non-military servicing, violence enticing (not all of them) Haredi Jews, who are granted a substituted life and strongly want to shape Judaism (not all of them, but as usual these are vocal), are one of the moral erosion factors under such tension. Due to the structure of the Israeli political system, their Shas party has yet always been part of any government to protect these privileges. Their numbers at the polls rise and their welfare grant is a compromise for Israel’s strange definition of a constitutional secular state centred on a religion.