It’s safe to say that if George W Bush was in his first term, he would now be heading for defeat. Safe, because we will never know: he’s in his second term and will never face the voters again.

That quirk in the US system, with its strict two-term rule, makes it hard to read the impact Hurricane Katrina will have on the Bush presidency. Nor is it much easier to tell how the disaster that drowned one of America’s best-loved cities will change the country itself. But both questions matter - especially for a wider world that has come to learn that what happens in the US affects everyone. Start with Bush himself. Weekend polls suggested 50-50 America has once again split down the middle, with Bush opponents disapproving of his abysmal non-performance last week while Bush-supporters stay loyal. That’s heartened Republicans who were bracing themselves for much worse numbers.

They find further cheer in their belief that Bush bounces back in a crisis. Attacked for his immediate response to 9/11, he turned that calamity into the defining moment of his first term. Privately, conservatives also wonder how much sympathy white, suburban America — the crucial middle ground all politicians covet — will feel for Katrina’s victims. One close-up observer describes what he suspects is a widely-held — if rarely articulated — view of those left behind in New Orleans: “They lived in a silly place, they didn’t get out when they should, they stole, they shot at each other and they shot at rescue workers.” If that’s the view, then Bush won’t suffer too badly.

Pessimistic Bushites see things differently. They reckon the sight of so many black Americans left destitute or dying while Washington idled will embarrass those same white suburban voters who, they say, feel uncomfortable at even a hint of racism. They also believe Bush and chief strategist Karl Rove can consign to the trash-can their long-term dream of peeling at least some African-American voters away from the Democrats. Bush had scored some small successes in that direction: now he can forget it. More directly, the charge of incompetence is deadly when applied to the White House: it could instantly diminish Bush, reducing him to a lame duck nearly two years ahead of schedule. The most immediate test will be in his nominations for what are now two vacancies on the supreme court. He has made one choice already; if he feels obliged to nominate a liberal or centrist as his second, rather than the red-meat conservative he would have preferred, that will be proof that Katrina has hobbled him.

What of America itself? Since the country’s founding, the US has oscillated between international engagement and isolationism. Sometimes it wants to look outward, sometimes in. The hurricane may well put Americans in the latter mood. As they look at pictures of US troops toiling away in Iraq, many will surely think: what the hell are we doing there, when we have so much work to do right here at home? Now it will be images of Katrina which are foremost in the public mind, replacing the four-year-old memories of 9/11. The “global war on terror” could well lose its place as the all-consuming, number-one priority.

Suddenly progressive Americans detect an opening, a chance to speak up for active government, even for taxing and spending. The hurricane has made their case immediate and simple: you can only neglect the public realm for so long. Do so for a generation and the levees will break - and an entire city will be washed away.

Still, it’s not obvious that the progressives will prevail. For one thing, Bush is not quite the no-spend conservative we imagine. The US government has actually expanded more under Bush than it did under Bill Clinton. It’s not just defence and homeland security: Bush has spent billions in traditional areas, including education - much to the ire of hardcore Reaganites. Louisiana may have suffered because its representatives did not have their snouts deep enough into the federal trough. After 9/11, Democrats made a similar demand and won the new Department for Homeland Security as a result. That is the department now blamed for handling Katrina so badly.

The left has another impediment, one that has dogged its opposition to the Iraq war: a lack of leadership. The most likely result is that America won’t rethink the size of the state so much as its efficiency. Simple competence could become the key political virtue. Step forward Rudy Giuliani, whose post 9/11 record contrasts so starkly with Bush’s errors last week. His chances of winning the Republican presidential nomination for 2008 look better than ever. There could also be a change in tone, with conservatives obliged to cool down the anti-government, low-tax rhetoric of old. Yesterday the Senate was due to debate a cut in inheritance tax that would have delighted the super-wealthy: mindful of the new mood, the Republicans quietly put it on ice.

A new political settlement has to be fought for and won. And that process is just beginning. —The Guardian