Naive Obama is living in the past over terrorism, says McCain

The Republican candidate's aides attacked Mr Obama for mooting the use of the criminal justice system to prosecute alleged terrorists - rather than detaining them indefinitely.

The Democrat contender countered by accusing Mr McCain of 'fear-mongering'.

'Fear-mongering': McCain speaks in Houston, Texas, yesterday

Long shadow: The September 11 attack on the World Trade Centre in New York

The candidates also traded blows over energy and the environment.

In a pointed reference to the devastating surprise terror attacks on New York and Washington on September 11 2001, McCain national security chief Randy Scheunemann said last night: 'Senator Obama is a perfect manifestation of a September 10 mind-set ... He does not understand the nature of the enemies we face.'

Former CIA director James Woolsey, who is advising the McCain campaign, said Mr Obama, 46, had 'an extremely dangerous and extremely naive approach toward terrorism ... and toward dealing with prisoners captured overseas who have been engaged in terrorist attacks against the United States'.

Mr McCain, 71, a Vietnam war veteran who graduated from naval academy three years before Mr Obama was born, has consistently touted his national security experience over his rival.

The comments from his camp came hot on the heels of a TV interview on Monday in which Mr Obama insisted the U.S. government could successfully crack down on terrorists 'within the constraints of our Constitution'.

He backed a Supreme Court ruling last week that said detainees at Guantanamo Bay have a constitutional right to challenge their indefinite imprisonment in U.S. civilian courts - a ruling derided by Mr McCain as 'one of the worst decisions in the history of this country'.

Mr Obama responded sharply to yesterday's comments from the McCain camp.

'These are the same guys who helped to engineer the distraction of the war in Iraq at a time when we could have pinned down the people who actually committed 9/11,' he told reporters on board his campaign plane.

Counterblast: Obama talks to journalists on his campaign plane yesterday

'This is the same kind of fear-mongering that got us into Iraq ... and it's exactly that failed foreign policy I want to reverse.'

Mr McCain also took aim at his rival over how to tackle America's energy problems, accusing him of recycling impractical ideas.

The Republican senator was in oil-rich Texas - President Bush's home state - unveiling an energy plan that includes a lifting of the moratorium on offshore oil drilling to help ease rising fuel prices.

Democrats and environmentalists oppose such a move but it will appeal to Americans weary of soaring petrol prices.

Mr McCain attacked Mr Obama's proposal to tax the windfall profits of big oil companies.

'If that plan sounds familiar, it's because that was President Carter's big idea, too,' he said.

Mr McCain also called for greater use of nuclear power, as well as alternative energy sources and greater conservation measures.

His remarks came a day after Mr Obama won endorsement from former vice-president Al Gore, winner of the Nobel Peace Prize for his work on environmental issues.

Mr Obama is calling for conservation and an intensive search for alternative energy supplies.