George W. Bush delivered his State of the Union address on Tuesday night with an awkward precedent behind him. He has become the first President since Woodrow Wilson in 1918 to lose control of both chambers of Congress in the sixth year of his presidency. What would in any case be a difficult lame-duck period will be considerably more challenging. Wilson spent his final 24 months in office desperately trying and failing to persuade Congress to support the centrepiece of his foreign policy, US membership of the League of Nations. Isolationist forces prevailed then. As Mr Bush seeks to win support for one last determined effort to bring real security and political progress to Iraq, he might fear a similar outcome.

For while only the second half of his speech dealt directly with Iraq, the blunt truth is that events in Baghdad will determine Mr Bush’s political standing in Washington. The domestic initiatives that he announced — on the environment, the budget and healthcare — were doubtless sincerely offered but were essentially defensive in character. The Democratic leadership on Capitol Hill has no interest in being the rubberstamp for the White House’s policy preferences. The new majority party has an agenda of its own — even if it is vague in a variety of respects — and it will not be shy in advancing it. Mr Bush’s weakness is that his partisan opponents have the votes on the floor of Congress. His principal asset is that he has a veto which is absolute provided that his political party sticks with him when he casts it.

Republicans may not, however, be as loyal as they once were if they sense that the President is unpopular. There will be no Administration candidate in the 2008 elections and there is no obligation for the Republicans who do make the race to defend Mr Bush if that will hurt them. Other congressional Republicans will also keep their distance if they believe that their re- election prospects are imperilled. The unusual solidarity of his party reinforced Mr Bush’s position during his first six years in the Oval Office. Anarchy in the ranks over his final two years could make for an ignominious political ending.

Mr Bush has thus effectively wagered his presidency on the success of his scheme to bring order to the streets of Baghdad and a sense of urgency to the Government there. While his plan is being sniped at by politicians, his authority as Commander-in-Chief remains considerable and it would be a rash and reckless Congress that cut off funding for US military operations in Iraq while the troops are on the ground. Mr Bush has been criticised for “escalation” in Iraq by sending in 21,500 more soldiers. Yet, in reality, as Lieutenant-General David Petraeus, his new commander in Iraq, has stated publicly, greater reinforcements could well be required to see this mission through. Mr Bush needs some early success that will make it possible for him to boost numbers.

For, at the moment, the President is trapped in a vicious circle. Setbacks in Iraq have sapped him on completely unrelated domestic issues as well as international relations. The solid expansion of the US economy has yielded no dividends for him. If he could convince Americans that Iraq were improving, his opinion poll ratings would almost certainly rise and his influence over legislation at home as well as matters overseas would be enhanced. President Wilson contended that “ absolute identification with one’s cause is the first and great condition of successful leadership”. Mr Bush, whose tenure is absolutely identified with Iraq, must hope that he was right.