In a January 23, 2014 interview, U.S. Secretary of State John Kerry told the Saudi-owned Al-Arabiya channel that the U.S. would use the military option if Iran backed down from its commitment under the Geneva document and restarted its uranium enrichment. He said: "If they decided they're going to throw this agreement away and go start enrichment again, sure, they can turn around. But guess what? If they do that, then the military option that is available to the United States is ready and prepared to do what it would have to do."
Kerry's statements enraged senior Iranian officials; some of them stated that the military option that Kerry was brandishing was nonexistent, some added that if Iran were to be attacked, its retaliation against American interests in the region would be harsh and would be aided by its allies across the world.
The following is a summary of statements by Iranian officials on the issue:
Supreme Leader Khamenei: America Lacks The Capability To Act Against Iran
In a January 26, 2014 speech, Iranian Supreme Leader Ali Khamenei dismissed Kerry's statements, saying: "Our top officials should pay attention to what [the West] is saying, because they smile and say that they are interested in negotiations, but at the same time, they say that all options are on the table. Well, what exactly are these options? What kind of action – or mistake – could they possibly take against Iran? If they are serious, they should exercise some self-restraint. All those people who utter this kind of nonsense must be stopped." (View the MEMRI TV clip of Khamenei's statements here.)
Previously, at a January 9 ceremony, Khamenei had also clarified to the U.S. that it is incapable of attacking Iran, saying: "If the Americans are not acting in a [particular] issue, the reason for this is lack of capability, not lack of hostility. They [the Americans] have said, 'If we could, we would dismantle Iran's nuclear industry' – but they cannot... The recent talks showed both America's hostility and its impotence."
IRGC Commander Ja'fari: Thousands Of Revolutionaries Worldwide Will Act If Kerry Implements This Military Option
Mohammad Ali Ja'fari, commander of Iran's Islamic Revolutionary Guards Corps (IRGC), said on January 25 in response to Kerry's statements that the U.S. "could never understand the extent of the offensive capacity of the Islamic Republic of Iran." He added: "Mr. Kerry must know that direct battle with the U.S. is the biggest dream of pious and revolutionary people across the world. Your threats offer our revolutionary people the best opportunity. The pioneers of Islam have been ready for years for the great and fateful battle... It is unlikely that the American administration would actually implement the ridiculous military option. The sun of the civilization of American imperialism has nearly set, and the American officials must not advance the crumbling of their own civilization by repeating this defeated strategy – that is, the use of military force. Mr Kerry, in the eyes of the true fighters, the U.S., with all its military force, is miniscule and shabby. Your military option will remain only on the table. Iran has no fear of this threat, and it and its revolutionary allies worldwide will unite to respond. I have recommended to the American statesmen that their words match their ability, and that they not set themselves up for ridicule by the revolutionary society of Iran. Thousands of revolutionaries across the world will act if you, Kerry, implement this option."
Iranian Army Chief Of Staff Firouzabadi: The American Military Option Against Iran Is A Joke
On January 28, Iranian Army Chief of Staff Hassan Firouzabadi said: "The military option that is today on the table in the U.S. has become a joke among the nations. It is best that the American officials examine the past, and if they themselves do not remember it, they should ask those who preceded them [in office] why they dared not attack Iran, despite the many threats [they issued], their deployment of forces, and their preparation of equipment."
Iranian Defense Minister Hossein Dehghan: Iran Will Cause Any Belligerent Enemy To Regret His Actions
Iranian Defense Minister Hossein Dehghan said on January 29: "Iran... is ready to confront any hostile measure from any aggressor... and will cause any belligerent enemy to regret his actions. Kerry's statements are nothing but a political bluff... The Americans know themselves that they are unable take any insolent step against Iran, and are well aware of Iran's defense capabilities... The continued uttering of ill-considered statements such as these increases the hatred of the Iranian nation and the nations of the region and the world against the U.S., and poisons the atmosphere ahead of future [nuclear] talks... It is puzzling that those who ostensibly [champion]... democracy and diplomacy still talk of using methods from the Middle Ages, and think they can safeguard their interests by means of force, oppression and aggression, disregarding the fact that the [medieval] era has ended. The use of this ill-considered rhetoric accelerates the U.S.'s decline."
Khamenei Advisor Velayati: The Military Option Is A Bluff
Ali Akbar Velayati, advisor to Khamenei, said on January 26: "This is not the first time that American officials utter these slogans. These declarations are more of a bluff. Obviously the Americans do not have this capability, because if they did, they would not have been expelled, completely weakened, from Iraq and Afghanistan. These slogans have no impact at all on Iran's determination to defend its nuclear achievements."
IRGC Official Javani: The U.S.'s Reiteration Of Its Threats Annuls Their Validity; Iran Can Target All American Interests In The Region
On January 26, Yadollah Javani, advisor to Khamenei's representative in the IRGC, called Kerry's statements on the military option a bluff, saying: "The Americans will undoubtedly not succeed in stopping the activity of [our] nuclear facilities... Their reiteration of their threats against Iran annuls the validity of these threats... Today, all the experts, strategists, and security and military analysts believe that the Americans are in no position to act militarily against a strong country like Iran and that these declarations are a bluff... The Americans know very well that if they make a mistake, Iran's response will be crushing... They will enter into a battle that they will not easily exit unharmed. Iran can target all the American interests in the region, and the Americans will never manage to suitably respond to the measures that Iran will take."
IRGC Senior Official: If Attacked, Iran Will Hit U.S., Israeli Targets
In a January 27 interview on Iranian TV, IRGC official Rastegar Panah threatened that, if attacked, Iran would use its long-range missiles against U.S. and Israeli targets: "What are the [American] military options? What do they want to do? What is this military option that they are repeatedly threatening to use as a trump card?... I believe that the Americans cannot attack us… We take upon ourselves a commitment that, with our nation, our people, and the values of our revolution, we will be able to respond in kind to whatever military action they take… Today, we have capabilities of long-range missiles, which can hit any necessary target. We definitely have the potential to hit any American or Israeli target, but we are not the ones who initiate wars. We have improved all our capabilities of deterrence, and the enemy knows this full well.”
Ayatollah Nouri Hamedani: Iran Will Chop Off America's Hand Before It Can Do Any Harm
Ayatollah Hossein Nouri Hamedani called Kerry's statements "infantile" and "silly," and warned him: "Know that before the U.S. manages to carry out a military operation, Iran's believing people will chop off its hand."
Majlis Member: The U.S.'s Military Bases In The Region Will Become The Slaughterhouse Of Its Troops
On January 25, Majlis National Security Council Committee member Mohammad Ismail Kothari said: "Obama himself knows better than anyone that the U.S. is in no shape to attack any country... How can the Americans, who were defeated in Syria, Iraq, and Afghanistan, stand fast against Iran's defense force?... [Addressing Obama:] If you make a mistake and act against Iran, be certain that we will fire with all our strength on your interests in the region... In the event of an American military attack on Iran, all U.S. military bases in the countries of the region will become the slaughterhouse of the American troops." 
Ayatollah Makarem Shirazi: Kerry's Insolent Rhetoric
Ayatollah Makarem Shirazi said on January 29 that Kerry had "become a despicable slave of Israel," and that "the West's ridiculous threats distance the Iranian nation from it and increase [this nation's] hatred for it." He added: "The hatemongering and ugly statement of the U.S. State Secretary, which was full of threats against Iran, displeased many, due to his insolent rhetoric. People are wondering how a man who does not know how to speak was appointed Secretary of State."
Iranian Army Air Force Commander: If The Americans Could Attack Iran, They Would Have Done So Already
Iranian Army Air Force deputy commander Amir Nasirzadeh noted that Iran was capable of doing severe damage to the U.S. military forces in the region, and of breaking their spirit. He added that if the Americans were capable of attacking Iran as they were threatening, they would have done so – meaning that they do not have the capability. 
Iranian Defense Minister: The Superpowers Fear Iran's Strength
Defense Minister Hossein Dehkan said: "Today the global arrogance [i.e. the superpowers, primarily the U.S.] fear the strength of the Islamic Republic of Iran and for this reason the form and style of their sanctions and threats are changing every day."
 Alarabiya.net, January 23, 2014.
 Khamenei.ir, January 9, 2014.
 Tasnimnews.com, January 25, 2014.
 Tasnimnews.com, January 28, 2014.
 ISNA (Iran), January 29, 2014.
 IRNA (Iran), January 26, 2014.
 Fars (Iran), January 26, 2014.
 See MEMRI-TV clip no. "IRGC Brig.-Gen. Panah: We Can Hit Any American or Israeli Target with Our Long-Range Missiles," January 27, 2014.
 Mehr (Iran), January 27, 2014.
 Fars (Iran), January 25, 2014.