An all-out war in the Middle East is hardly in anybody’s interest, yet it may happen, either as an escalation of a lower-intensity conflict, or because one of the sides miscalculates or is pushed into a corner.
A more localized outbreak, for example in Gaza or in parts of Syria, is considerably more likely, given the incredible buildup of arms and words in the region; in the mid-term, an American-backed or led attack on Iran is not inconceivable, as the wheels of both bureaucracy and rhetoric are clearly rolling in that direction.
Outward “signs” coming from the region are clearly not peaceful. Syria is becoming ever less stable, Hezbollah is restive, and the Gaza Strip has accumulated more weapons than ever before (and an all-but-open rivalry has developed between the ruling Hamas and the more tightly aligned with Iran second-largest militant organization there, Islamic Jihad).
Iran is seething – some of the latest developments include an attack on the British Embassy, a reported downing of an American stealth drone, and a couple of major explosions that reportedly obliterated a key Iranian missile testing base and damaged nuclear installations near the city of Isfahan. 
Israel is rapidly expanding its capacity to mitigate the impact of its enemies’ most formidable offensive weapons – missiles. A couple of weeks ago, the Israeli newspaper Yedioth Ahronoth reported, Israel received additional Patriot anti-missile systems from “a friendly country”. 
If confirmed, this acquisition would suggest an extraordinary step taken by the Israeli government in the face of an imminent threat (one memory it brings up is of the Gulf War, when the United States stationed Patriot missiles in Israel to counter the threat of Saddam Hussein’s Scuds).
Meanwhile, a third Iron Dome battery (against short-range missiles) has also reportedly been deployed by the Israeli Defense Forces in the past month or so.  During the last significant flare-up in October, Israel only had two functioning batteries, one of which failed to deploy immediately.
The Israelis have turned their anti-Iran rhetoric up to what seems a maximum in the past weeks. Given that past Israeli military operations relied on surprise, this circumstance likely suggests that an Israeli attack on the Iranian nuclear program is not imminent, but also that Israel is building up its case before the international community, justifying an attack in the future.
“We can’t wait and say – we’ll see if they have a bomb, and then we’ll act,” Israeli Defense Minister Ehud Barak commented recently, responding to American pressure to hold off from an attack. “What if by then we will not be able to act?”  In the past few days, Israeli Prime Minister Benjamin Netanyahu also directed a new round of veiled threats at Iran. 
Despite all the threats, Israel is understandably reluctant to engage in an operation on its own – especially right now, while it is still taking delivery of new anti-missile technology. A fourth Iron Dome battery, critical against the formidable short-range missile arsenal of pro-Iranian militants in Lebanon and Gaza, is expected early next year, to be followed several months later by a fifth (Israel needs around 15 for near-complete protection on all fronts, so every installation counts).
Some time in 2012, moreover, the new Arrow 3 exo-atmospheric anti-ballistic missile system, one of the most advanced in the world, is scheduled to be unveiled. It is as good an answer to Iran’s ballistic missile threat as any, and if that is forthcoming, it may be worth waiting for.
This timeline seems consistent, moreover, with the time frame for an Israeli attack by the second half of next year circulated by Israeli media and critics of such an attack, such as the influential former Mossad (Israeli spy service) director Meir Dagan, and attributed to Barak. 
In the meantime, while arming itself (and basking in the warmth of American generosity), Israel can sit back and allow a kind of war of attrition to go on. Sanctions wear down the Iranian economy, civil unrest wears down the Iranian allies in the region (specifically Syria, and indirectly Hezbollah), and sabotage and missteps wear down the Iranian nuclear and missile program. The much-rumored Israeli cyber-warfare program may yet offer new surprises, and set the Iranian military programs further back. 
A war in Gaza, however, is considerably more likely in the next months. It could be provoked (like several other recent violent episodes near Gaza) by Islamic Jihad, a militant organization considered Iran’s pawn and the major rival of Hamas in the Strip. There are increasing recent reports of tensions between Iran and Hamas, with the latter reportedly planning to pull out of Syria. 
As Israeli journalist Amir Oren suggests, Israel may also have a motivation to expedite a war in Gaza that it may see as inevitable, in light of the Egyptian elections and the likelihood that the next Egyptian government would be hostile to any Israeli military operation in the Strip. 
The United States, on the other hand, is coming under ever greater pressure to do something about the Iranian nuclear program. Its diplomatic initiatives are in disarray, new rounds of sanctions at the United Nations Security Council were rejected by Russia and China, and the American allies in the Middle East are showing increasing signs of impatience.
The military option is increasingly looking like the only way to resolve the crisis while maintaining a measure of control over the situation. A number of top American officials now publicly acknowledge that they are not sure if Israel will not surprise them with an air strike that could bring disastrous consequences. Saudi Arabia, moreover, is now all but publicly threatening to join the nuclear arms race if nothing is done against Iran. 
Though it can be difficult to gain detailed insight into American administrations – the current one included – it is a big and cumbersome bureaucracy that in many aspects functions according to broad policies that are hard to change and to resist, even by top officials.
Thus, whether we believe that former US president George W Bush was behind the National Intelligence Estimate in 2007 (which claimed that Iran had halted its nuclear weapons program back in 2003)  or not, it more or less tied his hands.
Similarly, the International Atomic Energy Agency report on Iran last month, which showed that estimate wrong, is bound to put pressure on current President Barack Obama to attack, whatever his personal inclinations are.
1. Report: Blast at Isfahan damaged nuclear facility, Ynet, November 30, 2011.
2. Iran’s Khamenei presents war scenarios, Ynet, November 25, 2011.
3. US may buy Iron Dome to defend ME bases, Jerusalem Post, December 1, 2011.
4. Barak: We can’t wait until Iran has nuclear bomb, Ha’aretz, December 3,2011.
5. Netanyahu’s history lesson hints at Israeli strike on Iran, Ha’aretz, December 4, 2011.
6. Former Mossad chief briefed comptroller about Iran strike plans, Ha’aretz, December 2, 2011.
7. Insight: Did Conficker help sabotage Iran’s nuke program?, Reuters, December 2, 2011.
8. Iran threatening to cut Hamas funds, arms supply if it flees Syria, Ha’aretz, December 5 2011.
9. Egypt turmoil may prompt Israel to strike Gaza, , Ha’aretz, December 27, 2011.
10. ‘Saudi Arabia may join nuclear arms race’, Ynet, December 5 2011.
11. Commentary: Was Bush Behind the Iran Report?, Time, December 4, 2007.