Writing in the Independent yesterday, columnist and comedian Mark Steel observed:

Governments and commentators keen on promoting a war against Iran should be stridently opposed, not so much because of the threat to world peace, but because their reasons display a shocking lack of imagination. The most common one is that Iran has "Weapons of Mass Destruction". How pathetic to pick the same excuse twice in a row.

In fact, not only have they picked on WMDs "twice in a row" but they've also gone for the fear-mongering classic: yes, a link to - wait for it - al-Qaeda! Yes, al-Qaeda!! Woo-hoo! Gotcha!

Neocon Clifford May, writing on the National Review's website yesterday, in a piece headlined "Al-Qaeda's Big Fat Iranian Wedding", claimed the Obama administration is

reluctant to articulate what has become indisputable: Iran and al-Qaeda are affiliated.

Hmm, where I have I heard something similar to that before? Oh, yeah, here, here and here. And whatever happened to all those claims of a link between secular Iraq and Islamist al-Qaeda? Oh, wait, this, this, and this.

May nods towards the recent headline-grabbing Sky News report which claimed that

Iran and al Qaeda's core leadership under Ayman al Zawahiri have established an "operational relationship" amid fears the terror group is planning a spectacular attack against the West.

Then there's the recent Telegraph piece which claimed

recent intelligence suggested Iran and al-Qaeda could attempt to find a common project in Europe, possibly targeting the London Olympics, which opens in July.

"Possibly" the Olympics? Well, I suppose anything's possible.

Yet, unlike in the run-up to Iraq, this time round some intelligence officials seem to be pushing back. Yesterday, Reuter's Mark Hosenball reported:

U.S. and European officials are downplaying allegations that Iran and al Qaeda have recently stepped up cooperation in preparation for possible attacks on U.S. and other Western targets. The officials, who are familiar with security issues, and private experts, discounted recent news reports about a possible new deal between Iran and what remains of al Qaeda's core leadership, now headed by Ayman al Zawahiri, long-time deputy to the late Osama bin Laden. "This should not be overblown," said one U.S. official, who asked for anonymity when discussing a sensitive subject. "This has been a very strange relationship for a decade or more," the official added. "We're not seeing any change in that relationship at the moment."

The Reuters report quoted another anonymous US official saying:

The relationship between al Qaeda and Iran is best described as complicated. The Iranians keep watch on what al Qaeda facilitators are up to. Sometimes the Iranians crack down on their activities; other times they don't. Al Qaeda moving fighters or money is one thing, while planning major terrorist attacks against the West from Iranian soil is probably something they won't allow. Al Qaeda is not necessarily friendly to Iran. . . Al Qaeda is sort of like a nasty parasite to Iran. It feeds off its ability to operate in Iran, with or without the Iranians' approval.

According to Bruce Riedel, a former CIA Middle East expert who has advised Presidents Obama and Bush, the history of Iran's dealings with al-Qaeda is "murky". Riedel has expressed doubts about the recent anonymous intelligence claims of a collaborative or operational relationship, noting how Iran has held al-Qaeda leaders under detention and house arrest over the past decade.

Another former CIA Middle East expert, Paul Pillar, notes:

It has been known for some time that al-Qaeda members have been inside Iran. It has been less clear just what the terms of their residence there have been. Most indications suggest that it has been something between imprisonment and house arrest. At least some of the al-Qaeda people in Iran have been able to conduct business of the group from there, but it is unclear again how much of this business is condoned or even known by the Iranian regime.

In fact, as Iran expert Trita Parsi notes in his new book, A Single Roll of the Dice: Obama's Diplomacy with Iran, senior Iranian officials had offered to hand over al-Qaeda figures to the United States and work, side by side, with the US government in its "war on terror" in the days and weeks after the fall of the Taliban in late 2001. They were rebuffed by the Bush administration which decided to instead include Iran in its "Axis of Evil".

But the much bigger and more important point is this: it is difficult if not impossible to believe that Shia-fundamentalist Iran and Sunni-fundamentalist al-Qaeda would want to work together, even if it was on the crude, self-serving basis of my "enemy's enemy is my friend". The mutual loathing, hatred and distrust between the two is just too high; the theological and political differences almost insurmountable. Then again, I wouldn't expect officials in the US intelligence or security communities to understand this key point: shamefully, as an investigation in 2006 discovered, many of them can't tell the difference between a Sunni and a Shia or even identify whether al-Qaeda is a Sunni or a Shia terrorist group.

Ironically, the country that has done most to boost and strengthen al-Qaeda over the past 12 months is not Iran but the United States: intervening in Libya allowed al-Qaeda-linked Islamist groups to take power while intervening in Syria to topple Bashar al-Assad will be a gift to Ayman al-Zawahiri. (Incidentally, if Iran and al-Qaeda are on the same side, then how can Iran and Syria be on the same side, given how Syria and al-Qaeda aren't on the same side? See how ridiculous this all becomes??).

Oh, and on a related note, here's the best piece of evidence to undermine all this new nonsense about an al-Qaeda-Iran "marriage": former al-Qaeda bigwig Anwar al Awlaki - who we were told by the Americans was the most dangerous and influential al-Qaeda terrorist in the world until his death last year - speaking about Iran in November 2010:

Al-Awlaki warned against Iran's military weaponry, saying that it aims at the Sunni Gulf states whose peoples will be the first Iranian targets. "O Sunni scholars, what is your plan to resist the spread of apostasy that is sweeping the region from Iran to Yemen? ... Are your guardians capable of resisting Iran? Iran spends its oil revenues to build its army, and your guardians spend money to protect and guard the American occupation from the blows of the mujahideen."

As the Atlantic's Max Fisher wrote, after reporting on the Awlaki comments:

Iran hawks and al-Qaeda-watchers have long suspected a possible connection for the understandable reason that the two groups share mutual enemies: the U.S., Saudi Arabia, Israel, and the military missions in Iraq and Afghanistan. But Awlaki's open renunciation of Iran, which comes despite all the strategic incentives he might find for supporting Iran, underscores just how ideologically incompatible al-Qaeda is with official state sponsorship of nearly any kind. Al-Qaeda's ideology is so extreme, and its ideological obedience so rigid, that it would be difficult for the group to tolerate, much less ally with, any regime other than the Taliban.

Nonetheless, people who should know better continue to spin this line about Iran and al-Qaeda. And why not? It worked so well last time round.

So, for instance, despite the fact that the 9/11 Commission report concluded that there was no evidence linking Iran to the 9/11 attacks, ludicrous claims continue to be made. I mean, check out this billboard image which appeared in New York late last year.

Salon's Glenn Greenwald summed up the hawks' simplistic, propagandistic mindset in a single tweet:

Iran and Al Qaeda, sitting in a tree, K-I-S-S-I-N-G

Yeah, but how about some proper evidence this time?