Iran: Threat of Nuclear War

Let's start with a little prelim on atomic weapons.
During World War II, the US-dropped uranium bomb killed 166,000 people. The later plutonium bomb on Nagasaki killed 80,000 people. US atomic weaponry has been later improved to include hydrogen bombs, which are said to have 10 times the explosive force of either uranium or plutonium bombs.
New York City has a population of 8 million people. One hydrogen bomb on New York City would kill almost 1/4 of the population.
Who has hydrogen bombs? The US, Russia, and probably China
Why are they not used? Primarily because of the philosophy of Mutually Assured Destruction (MAD). For example, if Russia were to unleash atomic weapons against the United States, the US would immediately retaliate in time to rain at least equivalent destruction on Russia. MAD works only when there are rational leaders. Insane or irrational leader for other reasons, such as religious fanatics would not be a deterrent.
What about countries having atomic weapon capability lesser than hydrogen bombs. In this case, we mean the old uranium and plutonium bombs. There is primarily one; North Korea, and Iran may be on its way. Leaders of these small countries may not be as rational as those of the larger powers and may be willing to take a chance that there would be no retaliation, if they used a uranium or plutonium bomb. Another possibility is a small group of religious fanatics, having no fear of death, purchasing enough fissionable uranium or plutonium to manufacture their own bomb and subsequently use it.
We can say without hesitation that the more fissionable uranium or plutonium available in the world, the greater the likelihood that it will find its way into an atomic weapon to be used to kill people; probably Americans.
The North Koreans already have an effective atomic weapon, having undertaken three tests. It is not known whether the test material involved enriched uranium or plutonium. Since the North Koreans already have the weaponry, it is impossible to backtrack and eliminate the threat. However, there is a greater chance that global major countries of greater economic power can control other countries, such as Iran, who have contemplated or are in only the initial stages of a nuclear program, probably also involving weaponry.
The Shah of Iran started a uranium enrichment program in the 1950s with the purchase and commissioning of a large number of centrifuges. That work of enriching uranium has been going on for more than 50 years, during which time the enrichment technology has undoubtedly been improved. Whether Iran is enriching uranium to a rather low state of enrichment for atomic power plant use or whether it is enriching uranium to a high degree of purity for atomic weaponry is unknown
The Obama Administration has for many years been attempting to convince the Iranians that they should not be enriching uranium past a certain high degree of purity, which would allow use in atomic weaponry. More recently, the British prime minister has sided with the Obama Administration in support of a program to let such negotiations proceed. Conversely, a number of US senators want to apply economic sanctions against Iran as a weapon to have them give up their enrichment program or at least be able to assure the negotiators that uranium enrichment would not take placed past a certain degree of purity, which would be less than required for atomic weaponry.
Since the Iranians have been working on uranium enrichment for more than 50 years, which during which time the US has and has had an on-off position on negotiation, it seems unreasonable that there is any hope that such negotiation will come to a reasonable conclusion without the introduction of additional factors; namely sanctions. It's somewhat surprising that the British, who are normally rather pragmatic, tend to side with the Obama administration in this pie-in-the-sky hope that Iran will comply with the request for reduced enrichment without such incentives.
The Washington Times has reported that Republican senators are brushing off Obama's warnings and avowing use of more sanctions. It is unclear to me what Obama's warnings are. Will additional sanctions anger the Iranian leadership, such that they would put more effort into uranium enrichment for an atomic weapon? Not likely. Iranian leadership already considers the US an enemy, as demonstrated by its promotion of terrorist action against the US. Does the Obama administration believe that the Iranians will sign an agreement not to enrich uranium past a certain purity, which would eliminate possibility of atomic weaponry? The Obama administration may believe that, but I believe that is not possible. There is no question that the Iranians will use every deceptive means possible to continue any program they desire on atomic weaponry, while trying to simultaneously convince the Obama Administration that they are cooperating. Let's remember that Iran is the land of liars, both in its people and its Administration.
Sen. Lindsey Graham is on the right track, but needs to go further. Economic sanctions should be immediately applied; not threatened.. Sanctions would then only be lifted as the Iranians completely give up the process of uranium enrichment or plutonium generation. The Iranians must also give completely open inspections to UN and US atomic energy inspectors. All equipment for uranium enrichment and plutonium generation must be dismantled and scrapped, so that it will not be available for start up at some future date. As the Iranians comply with these requirements, the economic sanctions can be slowly lifted and then reestablished if the Iranians deviate in any way from the accepted program.
The Iranians have claimed previously that the only interest they have in enriching uranium and generating plutonium is for use in atomic power plants, but any uranium enriching equipment could continue to enrich to levels suitable for atomic weaponry. For that reason, all uranium enrichment equipment must be dismantled and scrapped. Similarly, there should be no production of plutonium. Any materials necessary for atomic power plants could be purchased from major producers using funds available from oil exports.