John McCain insists that he has still not decided whether to run for president in 2008.

But as one of America’s most popular politicians sits in his Senate office, he gives the impression of a man already consumed by the decisions a President McCain will make.

He would make clear to the American people that military action against Iran is an option. Bombing? He nods. He would have Colin Powell in a McCain cabinet. Unlike President Bush - the man who beat him to the 2000 Republican nomination - he would veto any bill that contains "pork barrel" spending.

Combating global warming would be a top priority. In "about a year" Mr McCain tells The Times, "we will decide."

In the months after this November’s mid-term elections, he will ask himself: "Do my list of talents and strengths match up with the priorities of the American people?" For Mr McCain, it appears that question is already being answered for him.

The Vietnam War hero and outspoken Republican maverick, staunchly conservative but with extraordinary cross-party appeal, is currently the hottest ticket in Washington: frontrunner among his party’s early presidential contenders, more popular with Democrats than many of their own leading politicians, and with polls showing him easily defeating Hillary Clinton in a presidential contest.

One of the main reasons for Mr McCain’s bipartisan popularity is his trademark straight talking, a trait vividly on display during his interview with The Times. He does not employ the politician’s tools of artful dodge and dissembling. When he answers a question, he says what he thinks.

America has made "terrible mistakes" in Iraq. The consequences of failure there would be "catastrophic". The whole region, he says, would slide into "Muslim extremism".

The US, he says, is paying a price for its mistakes in Iraq in its inability to deal with the nuclear threat from Iran. Military action must always be the last option, but he warns: "There is only one scenario worse than military action in Iran and that is a nuclear-armed Iran."

Mr McCain was shot down over Vietnam and spent more than five years as a prisoner of war in the infamous Hanoi Hilton. Two of those were spent in solitary confinement, and during one he was consistently tortured. A scar on the left side of his face bears testament to the fact that he might have died of skin cancer five years ago had a facial melanoma not been removed in time.

He looks smaller and slightly more frail than he does on camera, and in 2008 he will be 72, older than Ronald Reagan when he became president.

But age and war have leant him a bracing candour. He disdains timidity. A long-time hawk - he was talking about "rogue-state roll back" years before Mr Bush entered office - he is still one of the most articulate defenders of the decision to invade Iraq.

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