For a date so important to the presidential calendar, the State of the Union address produces few memor-able lines. Presidential poetry tends to surface on other occasions — Ronald Reagan saluting the Challenger astronauts, John F. Kennedy’s inaugural address, Lincoln at Gettysburg. President Bush has also hit his own oratorical heights elsewhere. Three words, until this week, provided the exception. “Axis of evil” will for ever characterise his 2002 State of the Union. Now five others will echo through the years: Car-driving America is “addicted to oil”. This was his axle of evil moment.

Even if the message is hardly a secret, it was an interesting statement, as if Mr Bush was appearing at his first meeting of Oil Guzzlers Anonymous. If it required a Republican such as Richard Nixon to shake hands with Maoist China, perhaps only a former oil executive from Texas could put car-loving America’s relationship with the black stuff in telling context. For that we should be grateful.

Mr Bush’s remarks should not surprise us, though, for two reasons. He almost had his own “Man on the Moon” moment in 2003 when announcing $1.2 billion to research and develop a hydrogen-powered, exhaust-free car. But while promising a “national commitment” to that end, he produced no timetable. The second reason is that rising oil prices and new doubts about the security of supply have understandably prompted Mr Bush to harden his resolve. His goal, that in 20 years America must replace more than 75 per cent of its oil imports from the Middle East, is certainly ambitious. But it is necessary.

The consequence of reduced reliance on fossil fuels will be less environmental damage, but the White House is motivated chiefly by concerns for US energy security. It is those concerns that are most likely to persuade Americans to change their habits. They have plenty of reasons for worry. At its current rate of production Saudi Arabia will exhaust its plentiful reserves before Iran. Venezuela under Hugo Chávez is increasingly hostile to foreign oil companies and Washington in particular. China’s hunger for oil and oil diplomacy is obvious, and Russia has shown itself prepared to use energy as a political weapon. Oil production in the Niger delta is hamstrung by kidnappers. And drilling in the Alaskan National Wildlife Refuge, if ever approved by Congress, would cut US crude imports by only 2 per cent, to 60 per cent, of total consumption by 2030.

Mr Bush is right that the solution will require advances on all fronts, from safe nuclear energy to zero-emission coal-fired plants, wind and solar technologies and cleaner, more efficient ethanol. On Tuesday night he talked only of carrots. The lessons of California’s environmental advances, though, are that fiscal sticks need to be deployed. Unless we are all encouraged to reduce fossil fuel use, there will be only a limited market for new fuels. Mr Bush has taken the first important step of admitting the problem. But as any addict will attest, there is no gain without pain.