There isn't going to be anything resembling a war in the region, only very one-sided military action by a rogue nation. If anything happens it'll be Israel, with its scaled-down version of the US army, attacking one of its infinitely weaker neighbours. It won't spread any further than that, China, Russia etc. would not get involved. Absent any Israeli attack there'll be no attacks on Israel by any other country. America doesn't want Israel bombing Iran while they have tens of thousands of troops in Iraq and Afghanistan in situations Iran could make much worse for America should they want to do so. Israel would have to get permission from America to overfly Iraq in order to attack Iran so if it does happen the world would know that America agreed to the bombing. This would have big consequences in Iraq/Afghanistan.

And bombing Iran wouldn't prevent them getting a nuke, quite the opposite in fact. Right now Iran aren't building a nuke and the only thing that would make them do it is an Israeli and/or US attack. Even if Iran started building a nuke tomorrow attacking them would only delay them building one, not prevent it. Also nobody is going to invade Iran. America couldn't handle an insurgency derived from 5 million Iraqi Sunnis, they had to agree to withdraw after failing in their objectives. No way could America fight an insurgency derived from 50 million pissed-off Iranians who only kicked America's imposed dictator out a generation ago. Plus you have the oil issue, nobody wants skyrocketing oil prices with such a fragile recovery. Any attack on Iran probably is years away, but who knows with a rogue regime in charge in Tel Aviv.

More likely is Israel bombing Lebanon, Syria, or the Palestinians again, and that's probably a reverse order of likelyhood. As in the past this is most likely to happen before a general election in Israel or at a point when the government needs more political capital or prevent what exists of the Arab-Israeli peace process making progress.