The Pentagon unveiled its proposals for a bigger army in the “long war” against terror yesterday as President Bush began the hard sell for his new strategy of sending 22,000 more troops to Iraq.

Robert Gates, the Defence Secretary, outlined proposals for a permanent increase in the size of the Army and Marine Corps at a likely cost of $15 billion (£7.7billion) a year.

He recommended adding 92,000 troops over five years, bringing the Army to 547,000 soldiers and the Marine Corps to 202,000 service members.

“We should recognise that while it may take some time for these troops to become available for deployment, it is important that our men and women in uniform know that additional manpower and resources are on the way,” he said.

After missing recruitment targets in 2005, the Army lowered standards and doubled enlistment bonuses. Last year it raised the maximum age for recruits from 35 to 40 and then to 42.

It also relaxed rules outlawing visible tattoos above the neck and ensured that candidates who are a little overweight or suffer from attention deficit were no longer turned away.

An advertising campaign that began in November replaced the previous slogan of “army of one” which carried unfortunate connotations of a recruitment crisis. The new slogan is “Army Strong”.

Other, less successful, recruitment efforts have included writing to 5,100 officers who had recently left the service. The letters, sent out at Christmas, included 75 to officers killed in action and 200 more who have been wounded. But perhaps the most controversial measure to address recruitment shortfalls is the offer of automatic citizenship to foreign nationals recruited in the Army. Since Mr Bush signed an order in 2002 formalising a fast-track to citizenship through military service, more than 25,000 immigrants have done so and a further 40,000 are eligible.

Mr Gates said that he did not know how long the increase in troop levels in Iraq, announced Bush on Wednesday night, would last. They will bring the total number of US soldiers to around 154,000. “It’s viewed as a temporary surge, but I think no one has a really clear idea of how long that might be.” Mr Gates said.

An AP/Ipsos opinion poll yesterday suggested that 70 per cent of American voters opposed sending more troops to Iraq. Barely a third of those surveyed now say that it was right for the US to invade Iraq.

Leading Democrats, as well as some Republicans, signalled strong opposition to Mr Bush’s strategy — funding for which could yet be blocked by Congress. Senator Barack Obama, a likely 2008 presidential candidate, said: “We’re not going to babysit a civil war.”

Senator Hillary Clinton, the frontrunner for the next Democratic presidential nomination, said Mr Bush’s Iraq policy “has been marred by incompetence and arrogance”, adding: “He will continue to take us down the wrong road — only faster.”

Mr Bush has said that continued US support is conditional on the Iraqi Government meeting a series of promises. Although he has not set a specific timeframe, pledges include taking on the powerful Shia militias and allowing troops to operate unfettered by political and sectarian interference.

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