US officials in Baghdad and Washington are expected to unveil a secret intelligence “dossier” this week detailing evidence of Iran’s alleged complicity in attacks on US troops in Iraq. The move, uncomfortably echoing Downing Street’s dossier debacle 2003, is one more sign that the Bush administration is building a case for war.

Nicholas Burns, the senior US diplomat in charge of Iran policy, says Washington “is not looking for a fight” with Tehran. The official line is that Washington has made a decision to “push back” against Iran on a range of fronts. Primarily that means Tehran’s perceived meddling in Iraq, where its influence with the Shia-led government and Shia majority population appears to be increasing as Washington’s weakens. State Department Spokesman Sean McCormack said this week the administration had a body of evidence implicating Iran in sectarian attacks against Iraq’s Sunni minority.

The CIA and Pentagon are also touting intelligence that “Iranians are smuggling into Iraq explosive devices, mortars and plans to wipe out Sunni Arab neighbourhoods”, The New York Times said. Officials would make a “comprehensive case” this week. But Bush has already acted on information received. He said on Monday that he had ordered US forces, in effect, to kill or capture Iranian “agents” targeting Americans in Iraq.

Hassan Kazemi Qumi, Iran’s ambassador to Iraq, ridiculed “sectarian maps” and evidence the US military said it had obtained during a raid on a Shia compound in Baghdad. He repeated Tehran’s contention that Iranians were in Iraq to help with “security problems”. Barham Saleh, Iraq’s deputy PM, has said the US and Iran are turning his country into a “zone of conflict and competition” and suggests they take their fight elsewhere.

Israel is also pushing the intelligence case while upping the ante, claiming to have knowledge Tehran is a year or two away from basic nuclear weapons-making capability. In a BBC interview last week the former prime minister Binyamin Netanyahu compared President Mahmoud Ahmadinejad’s regime to the Nazis. Speaking in Davos the deputy PM Shimon Peres, demanded immediate regime change or failing that, military intervention.

The US “push back” against Iran comprises many other elements. Unconfirmed reports suggest Dick Cheney, the US vice-president, has cut a deal with Saudi Arabia to keep oil production up even as prices fall, to undercut Iran’s main source of foreign currency. Washington is pursuing non-UN global financial sanctions against Tehran; encouraging and arming a “new alignment” of Sunni Arab Gulf states; and highlighting Iran’s role in “supporting terrorism” in Palestine, where it helps bankroll Hamas, and Lebanon, where it backs Hizbullah.

Almost any one of these might produce a casus belli. When taken together, despite official protestations, they point in only one direction. Bush, an American commentator suggested, is “once again spoiling for a fight”. —The Guardian