George Bush will embark this week on the toughest phase yet of his presidency, with a Democratic-controlled Congress arrayed against him for the first time, ahead of his expected - and certain to be controversial - decision to send more US troops to Iraq.
After spending much of his Christmas and New Year break at his Texas ranch consulting senior advisers over the various options on Iraq, Mr Bush is likely to make his announcement next week.
But whatever he decides will face intense scrutiny in the new 100th Congress, where many Republicans, as well as Democrats, argue that the administration should start withdrawing troops, rather than sending servicemen into a civil war which any American presence, however large, is powerless to control for long. Those tensions have been exacerbated by the sectarian taunts exchanged at Saddam Hussein's execution on Saturday.
Mr Bush has been careful not to tip his hand. But every sign is that he is leaning towards a temporary "surge" in US strength - 20,000 to 30,000 is the figure most commonly mentioned - above all to regain a grip on Baghdad.
In doing so, he would be sending another signal that he is not inclined to give ground to his critics, or embark on the radical shift in strategy his opponents are demanding.
A taste came last month with the tepid White House reaction to the report of the Iraq Study Group chaired by the former Republican Secretary of State, James Baker, which urged an early start to troop reductions, and the opening of diplomatic contacts with Iran and Syria. The latter step has been ruled out while, in an apparent rejection of a hasty pull-out, the new Defence Secretary, Robert Gates, has warned that an American defeat in Iraq would be "a calamity".
But opposition in Congress, even among Republicans, is strong. Richard Lugar, outgoing chairman of the Senate Foreign Relations Committee, has expressed reservations about a force increase in Iraq, while Chuck Hagel, the Nebraska senator, said such a move would be "folly".
Scepticism will abound too at the Foreign Relations Committee hearings on Iraq, due to start on 9 January and run for three weeks. Joe Biden, the panel's Democratic chairman, says he is "totally" opposed to a troop increase, adding that one would be "contrary to the overwhelming body of informed opinion, both by people inside the administration and outside the administration".
Although a 30,000 increase to the existing deployment of 145,000 troops is feasible, by delaying rotation of units and lengthening tours of duty, many senior generals say it could only be temporary, given the existing overstretch of the military. At some point the troops would have to leave, irrespective of the level of violence at the time.
New figures show that 1,930 Iraqi civilians died in December, which was also the deadliest month in two years for US servicemen, taking the lives of 111 soldiers. Since the 2003 invasion, more than 3,000 have been killed and about 25,000 injured. More American troops would merely invite more casualties, critics contend.
The President's new approach also would signal the abandonment, at least temporarily, of the strategy of turning security over to Iraqi forces. This was the policy favoured by General George Casey, the highest-ranked US general in Iraq.
But for all the Pentagon claims that more and more Iraqi units were now trained for the job, the violence has only increased.
General Casey is now likely to be removed, probably within the next two months, while Lt-Gen John Abizaid, the head of Central Command and in overall charge of the Iraq war, is also due to step down.
After the post-midterm election replacement of Donald Rumsfeld by Robert Gates at the Pentagon, Mr Bush will in effect have installed an entire new leadership of the war.