Though that still does not take into account the possibility of a accidental war, one which is caused by a miscalculation of one side or another, that could lead to a nuclear exchange, the more countries that have nukes the higher the probability of something like this happening. It and other close calls have happened at least four times to my knowledge during the cold war, between the US and the USSR, and those countries have extensive safety measures in place, now imagine five+ countries in the middle east with nukes, the odds greatly increase.
This is exactly why we (most of the world) don't want Iran with a nuke, Lets look at the history of this conflict, India gets the bomb, Pakistan is scared shitless, They work hard to get the Bomb, they steal nuclear centrifuge tech and get the bomb in 1997, India ramps up production of its nuclear arsenal, Pakistan and India now both produce dozens of warheads a year with no sign of slowing down. Pakistan then sells its nuclear know how to Iran, Libya, Syria, North Korea, and Myanmar. Now lets imagine all this happens with several unstable states in the middle east. So yeah Pakistan with the bomb is a nightmare, that doesn't mean we need to go and encourage the situation elsewhere, as you stated we have enough to worry about with Pakistan and India.
PS
akistan's military has unreliable control over its nuclear arsenal, since it doesn't use the safeguards most countries do to prevent accidental launching theoretically a rouge officer could launch their missiles, or sell them.
This might be true, however Pakistan is a unstable region but that does not mean they have "bad"control over their arsenal.
Sure security can be improved and this is being done:
The Pentagon's Secret Plans to Secure Pakistan's Nuclear Arsenal | Global Security Newswire | NTI
Keep in mind the US did not have their arsenal secure without trail and error it took a long time for the US to ensure a fail save system for their nukes.
In the US history there have been loads of errors and near launches just because their system glitches as has been pointed out in numerous discovery and other tv programs.
In short said there is always a serious risk that something goes wrong.
Imagine that a computer or sat detects a launch and mistakes it for a nuke...this has happened in the past and i am sure similar things can happen again.
So claiming that Pakistanis control over its nukes is crappy is just not true.
They have a lot of problems and they have serious instability issues but i am VERY sure that the leadership will NOT allow their nukes to be compromised.
Personally i have to say that it troubles me just as much to see the US having Nukes as well as it does that the Chinese, Russians and all other nations have them.
And as long the 3 major powers US, Russia and China (Not counting France, UK and others) do not come to a full agreement to totally disband their nuke piles they cannot demand that a other nation does not get them.
Sure if Germany gets a nuke or any other reliable and solid nation then its a whole different ball game then having some rogue nation with dictator regime get one..i understand that and i also understand that the aim is to stop all nukes.
Fact remains that every nation can build one because the other nation still have them....its a circle that goes round and round.
And its my firm believe that Nukes will remain active (maybe in much smaller numbers) but the major powers will always keep a few around....
As it adds greatly to for example diplomatic power.
Imo the US would not be able to play its role it is playing today without the backup of its nuke subs and silos.
And how weard this might sound but the fear of nukes and the dangers from it are also its biggest security and fail save.
As launching them will mean mutual destruction so technically speaking nukes contribute greatly to stability and security...one way or another.
In regards to the US invading Iran i do not see that happen anytime soon, however the option is there as a last resort.
According to the news Israel has a credible plan to execute military actions against Iran if it comes to it and the US will back that 100%.
However if for whatever reason things go out of hand and personally i do believe that if Israel hits Iran that Iran will fight back with Rockets and medium range missiles.
Short said it will force the US into war one way or another (Small or massive scale it does not matter)
So are there plans to invade Iran ...not really
Are there preparations to make a large scale military action possible? I think yes.
Maybe i say this wrong but the Israeli government even make a plan to go to the toilet and i am sure they are on top of this and i am very sure that they can surgical strike Iran at any time at any moment and do it with succes.
However i have to say that Iran does have the endurance to overcome a attack by Israel.
In the Iraq war it has been shown how resilient Iran can be it also have been shown that even with the low tech they can be effective and can achieve strategic goals.
Israel on the other hand does not have that resilience.
A few medium range missiles targeting the capital will destroy Israeli economy and will disrupt the nation greatly.
A few days ago there was a documentary on the dutch TV where they interviewed some very known and high placed people including officers and pilots who did the raid on Iraq and Syria.
They ain't afraid for the attack itself and the outcome...they say its simple Israel will win that attack and achieve its goals and there is ZIPPO that Iran can do about it.
However the window of attack closes as Iran's installations are getting better protected by the day.
So it might take 2 or 3 years before Iran could make a bomb however to stop the program itself you have to make sure you can hit the targets in the first place and thats a real issue since the layers of protection grow day by day so sooner or later Iran will be having immunity against Israeli conventional arsenal.
Another thing is: The US wants to stop Iran from getting a bomb, Israel however wants to avoid that Iran gets nuclear tech in the first place which is a HUGE difference.
So the so called red line or point of no return for Israel is much closer then that of the US.
Anyway as has been said on the TV by the end of 2012 (Or even sooner) Iran will enter the immunity zone where Israels arsenal cannot harm the installations anymore and thats exactly why Israel pushes so much to get the international community to stop Iran or Israel will be forced to make the hit.
And they will get the job done, HOWEVER those interviewed officers and ex officers said that after the attack the real problem starts.
You can bomb Iran all day and they will survive, however you drop a dozen missiles on key points and cities in Israel and its all over.....
And thats the points when the US will be forced to jump in.
Simply said Israel its armed forces are superior to Iran however the size of Iran is its biggest ally as Israel alone cannot finish what it starts.
Specially with all those hardcore rebel groups in Gaza and Palestinian breathing down their necks.
And a attack upon the installations of Iran will activate every rebel group in the region to come down on Israel.
That is nearly literally what has been said during that documentary from netwerk or nova if i am not mistaken.
So technical speaking we already know upfront that the US must have serious plans in terms of military actions against Iran or even full scale invasion plans.
Because the US military knows exactly that if Israel makes the hit that the US must and will jump in.
Thats exactly what Obama said after the last meeting between him and the Israeli minister.
I quote: We will have Israels back always....
On a personal note: Its not always the strongest who prevail and its not always that the weakest lose.
Its a matter of variables and opportunities to determine of a victorious outcome is possible and to be honest Iran is one of those nations you can bomb back to the stone age and still they will be able to recover and to put up a fight.
The middle east has thousands of years of violence its in their culture and regardless the outcome of those many many wars that have been fought in the middle east the region always recovered and played a prominent role in history and remain to do so.
And thats exactly the point with Iran its size and its vast resources and its large population will ensure that Iran cannot be taken down that easy.
Even the US with all its might cannot just walking into Iran and win a war.
Its just not that simple.
If Iran wants a bomb then they will get it sooner or later, its the question what prize are they willing to pay to achieve that goal, and what effort is the international community willing to bring in to stop it?
And in those odds it favoures Iran greatly...