Neither was Poland at the start of WW2, or Serbia in WW1, but there was a very quick knock-on effect. If Iran was attacked, then other middle eastern countries would become involved, such as Syria, Lebanon and Gaza. And its likely anything involving Iran would involve Israel, which would polarise most of the other countries in the region and quite possible drag Europe into things, which in turn will most likely drag in Russia. And with most of the great and super powers tied up else where, other countries (like North Korea for example) might try and further their own aims. A North Korean attack would drag in South Korea, Japan and China. Oh look, the war now spans 4 continents. 

WW1- Serbia was allied to Russia who were allied to the UK and France. Russia had an obligation to protect it. Austria Hungary was allied to Germany who were allied to the Ottomon Empire...you can see how that went out of control. Iran on the other hand is militarily allied to Hamas, Hezbollah and Syria only one of which is a country. There is no way they could start WWIII and no other power such as Russia or China would come to Iran's aid militarily. The US and Israel would decimate Iran conventionally.

WW2 started at different times for different countries. For the UK we say 1939, ask China they'll say 1937, Russians 1941 and so on. Again same thing, no one will come to Iran's aid militarily, Iran has no military pact with anyone.

If anyone makes a move on Iran, especially if its the US, Israel will be with them, which will drag in all the anti-Israel countries in the Middle East regardless of what military pacts they do or dont have. If you read my last post again you can see how it could have a domino effect to drag multiple other countries from across the globe into the conflict.

I think you don't understand the geopolitical reality of the situation in the region. The US is by far the dominant power even if Iraq and Afghanistan has wounded it. All the (Arab/Sunni) Gulf countries are under the security umbrella of the US. Saudi Arabia is the main power out of the Gulf nations. It fears a powerful Persian Shia nation that could rival it's position. Israel also fears a powerful non allied Iran. If Israel bombed Iran none of them would come to Irans aid. Furthermore Jordan and Egypt have peace treaties with Israel. Syria wouldn't dare make an obvious move but Iran would of course retaliate using asymmetric warfare methods. The domino effect worked in the last two world wars because of military pacts and each side were very powerful so the war dragged on. In this case the military balance is overwhelmingly one sided. I remember when the Kosovo conflict was taking place and people were saying the same thing then.

Israel has attacked it's neighbours repeatedly over the last few decades. We are all still here.

french is more romantic.

how jealous can you be that your first lady looks like a man under a black sheep and that the first lady of the other party is a top model... apparently a lot!

Iran can't be invaded, they need a freken revolution.

Invasion would lead to armed factions left and right... revolution would lead to a more stable country me thinks.... though the fanatics might just kill people for the sake of it...