And at least some of its supporters think John McCain is the presidential candidate best suited to continue that trend.

“Al-Qaeda will have to support McCain in the coming election,” said a commentary posted Monday on the Qaeda website — al-Hesbah. It said the Arizona Republican would continue the “failing march of his predecessor”, President Bush.

The web commentary was one of several posts by Taliban or al-Qaeda-allied groups in recent days that trumpeted the global financial crisis and predicted further decline for the US and other Western powers. In language that was by turns mocking and ominous, the newest posting credited al-Qaeda with having lured Washington into a trap that had “exhausted its resources and bankrupted its economy”. It further suggested that a terrorist strike might swing the election to McCain and guarantee an expansion of US military commitments in the Islamic world.

“It will push the Americans deliberately to vote for McCain so that he takes revenge for them against al-Qaeda,” said the posting, attributed to Muhammad Haafid, a longtime contributor to the password-protected site. “Al-Qaeda then will succeed in exhausting America.”

It was unclear how closely the commentary reflected the views of al-Qaeda leader Osama bin Laden, who has not issued a public statement since the spring. Some terrorism experts said the support for McCain could be mere bluster by a group that may have more to fear from a McCain presidency. In any event, the comments summarised what has emerged as a consensus view on jihadist sites, said Adam Raisman, a senior analyst for the Site Intelligence Group, which monitors Islamic web pages. Site provided translations of the comments to The Washington Post.

“The idea in the jihadist forums is that McCain would be a faithful ‘son of Bush’ — someone they see as a jingoist and a war hawk,” Raisman said. “They think that, to succeed in a war of attrition, they need a leader in Washington like McCain.”

Islamic militants have generally had less to say about Obama. Leaders of the Iranian-backed group Hezbollah expressed a favourable view of Obama during the primary campaign but later rejected the Democrat after he delivered speeches expressing support for Israel.

In an e-mail response, senior McCain foreign policy adviser Randy Scheunemann noted that al-Qaeda leaders have repeatedly said that America “did not have the stomach to fight them over the long haul”, which the Arizona senator has pledged to do. “Whatever musings and bravado on radical websites the Washington Post chooses to quote, the fact remains that only John McCain has the experience, judgment and fortitude to lead a country at war,” he said. The Obama campaign declined to comment on the Web postings. Both the Bush administration and the two major presidential campaigns have rejected any suggestion that the economic downturn will undermine the country’s fight against the al-Qaeda.

From shortly after the September 11, 2001, al-Qaeda attacks to last year, US defence spending rose from 3 to 4 per cent of gross domestic product, but it remains far below the 45-year average of 5.5 per cent. The Pentagon’s budget for fiscal 2009 is $527 billion, a figure that does not include Iraq and Afghanistan war costs, which have totaled more than $800 billion since 2001.