A war with Iran has three drivers:
- It is building a nuclear weapon. The Israeli security lobby is going nuts.
- Iran is sitting on top of the world's 2nd largest reserves of natural gas (behind Russia). Given how important natural gas is to future global energy needs and the need to hedge Russia's control over the global market, this can't be allowed.
- The US defense industry needs a new way to drive spending now that bin Laden is dead. Iran is now at the top of the list (China/Cyberwarfare is next on the list).
With these drivers in place, all that is needed to is to remove barriers to a conflict.
First, and this is a prerequisite for any state vs. state conflict in the 21st Century, Iran needs to be disconnected from the global economic system. That is now happening. New sanctions (shades of Iraq) are truly disconnecting Iran, even from China.
The last impediment? An international mandate for a war with Iran (or at least, a major bombing campaign to destroy facilities and infrastructure). That effort is in process, but it's not going so well. China apparently doesn't like the idea (it's hard to get China to agree on stuff like this when they are being used by the US Defense Industry as its next boogeyman).
However, things are different on the Iranian side. In Iran, the crunch has begun.
The effects of these sanctions has ALREADY created hyperinflation in Iran (which will soon unwind the entire Iranian economy and create political chaos). Add to this a weekly drumbeat of special operations/drone assassinations and bombings/explosions aimed at Iranian senior personnel/facilities within the Iranian nuclear/missile program (which means they will be unlikely to build a bomb before economic disaster rolls them).
The only option for Iran?
Diplomacy? That isn't going to work. Most of the world is already planning on the economic spoils a new Iranian regime would unearth. They have no interest in saving the current regime.
Stop developing a nuclear bomb? That wouldn't work. The train on a regime change in Iran has left the station and it won't stop until it happens.
Military action? Nah. Iran's military is a waste of money, given its status as a speed bump to western military action. A move to block the straights of Hormuz would be a military disaster.
Systems disruption? Yes. A global effort to disrupt energy systems would put pressure on the west to relent. The only real question is how they will disrupt it (without using overt military power).