For President Obama, the debacle of the first round of the Afghan elections has had a silver lining: it has bought him more time before he has to say what his plan for the country is. It has not made his options any more attractive, but it is very likely to produce a demand for President Karzai to be much more helpful to the US — and a refusal to commit many (or any) more US troops if he is not.

Obama, more than twice as popular as George W. Bush when he announced the Iraq “surge”, is not in as tight a corner as his predecessor but the pressures to make this decision fast are huge. The voting chaos has raised with new venom the Vietnam comparison — the fear that the US is supporting a leader with no broad legitimacy. Obama needs to respond urgently to his senior commander, General Stanley McChrystal, who has warned of failure and called for 40,000 more troops. Britain and other allies, their soldiers killed almost daily, are frustrated and angry at the strategic vacuum in Washington.

US officials admit that it is an embarrassment that Obama made a speech in the spring that was supposed to define US strategy, another in the summer, and must do so again now. Advisers are falling over themselves to say that Obama has not yet decided on his response, but two themes emerge.

First, the Obama team clearly intends to be tougher on Karzai, demanding a say in the choice of key ministers and provincial governors. There is bitterness about Karzai’s lack of co-operation, given the US troops and billions of dollars of American aid, and there is new, sharp awareness that Afghanistan is a country rich in resources, after US geological surveys of its exceptional mineral wealth in March and its oil and gas two years ago.

America’s pursuit of more influence over key posts could mean that it would back a deal between Karzai and Abdullah Abdullah, his main rival, to form a unity government and pre-empt the November 7 run-off. The Constitution allows the poll to be scrapped up to the day before it is due to be held and top officials in Kabul and Washington reckon that this might well happen — not just because of the horrible logistical problems a run-off entails, but also because the contenders might prefer the certainty of a deal. Even though Karzai is expected to win, he cannot be sure by how much.

Second, Obama’s team is urgently trying to draw up plans to turn security over to Afghan forces, still too few but 70 times cheaper than US manpower. In theory, the McCrystal call for a 40,000 increase is achievable, several advisers say — the recession has helped with recruitment. But his call comes on top of a temporary rise of 22,000 announced in the summer, already a strain on the National Guard and reservists, and which depends on a reduction of numbers in Iraq.

The greater problem is that McChrystal’s report, some think, does not say how to escape from what one called the “2009 quandary” — that this year the US has more than doubled the number of troops in Afghanistan, to 68,000, for no solid claim to progress.

Whatever Obama eventually says will be dominated by the headline number of how many — if any — more troops he will send. But advisers are keen that this time he is not boxed in and that there is room for future changes. He will assert that US commitment depends on progress on governance and security — a warning to Karzai. He will emphasise the risks and say something along the lines of “we need time to get this right”.

In scripting this cautious, conditional response, advisers are trying to create space for Obama, if he wants, to announce something that could fall far short of the McChrystal 40,000.

Times Recommends

• Bank charges hit us for being human
• Sorry, Father, thou still shalt not steal
• The shed where Santa’s failures go to die