IN her first fortnight as John McCain's running mate, Sarah Palin did not answer a single tough question. She told People magazine that she sometimes has to "put down the BlackBerries and pick up the breast pump" in the middle of the night. She addressed huge crowds, without ever straying from the themes she laid out at the Republican convention. Her record was scrutinised, but her diary stayed shut.

McCain's spokesman Rick Davis told Fox News that until "we feel like the news media is going to treat her with some respect and deference, it would be foolhardy to put her out in that environment".

A New York Times editorial responded "it is well past time for Sarah Palin to fill in for the voting public the gaping blanks about her record and qualifications to be vice-president".

With such pains being taken to shield her from the press it was inevitable that Palin's first serious interview would be hyped out of all proportion. The scoop everyone wanted turned out to be little more than familiar talking points, plus a few new lines learned by rote.

At the end of two exclusive chats with Charles Gibson of ABC News, all that can be said for certain is that Palin is the most polarising political figure for a generation. Her popularity with conservatives is wide and deep. The fear she strikes into Democrats is profound.

Two months before an election, there is no room for nuance. To the left, the conversations proved that Palin is way out of her depth and would be a catastrophic vice-president, turning the USA into an international laughing stock.

To the right, she gave strong answers on Israel, Islamic terrorism and energy policy, stood up to a bully and exposed liberal media bias once and for all.

Palin spent a week preparing for the interview with two of McCain's senior foreign policy advisers, so it was hardly surprising that her answers sounded scripted. Pressed three times, she refused to say whether she would support an Israeli attack on Iran. She sounded a belligerent note about Russia, without quite threatening to invade. Her manner was combative, leaning forward with jaw set firm, but she also called her host "Charlie" a lot.

She was more comfortable with domestic policy the following night in Wasilla, although her prescription for the ailing economy was a weak reiteration of Republican orthodoxy. "Government has to get out of the way," she said, promising to reduce taxes, control spending and make efficiency savings everywhere.

On gun ownership, abortion and homosexuality, she straightforwardly expressed her personal views and sounded perfectly at home, which she was.

Her one major slip came when Gibson asked whether she agreed with the Bush doctrine. It was clear she had no idea what he was talking about. She stumbled and stalled so much that he eventually spelled out the philosophy of anticipatory self-defence for her. To liberals, it was a frightening display of ignorance. To conservatives, it was a hatchet job laid bare.

"This one is going to backfire on the media once again," read a typical comment at Michelle Malkin's influential right-wing blog. "Women watching that are only going to see him trying play gotcha' with Palin and her fan club is going to grow. What a jerk."

McCain's latest advert portrays the hunter as the hunted. Democrats scouring Alaska for evidence to use against Palin are represented by wolves, while a voiceover warns that "as Obama drops in the polls, he'll try to destroy her". She has been the unremitting focus of news coverage since the conventions, both positive and negative, but the campaign's response has been an aggressive withdrawal.

Palin is phenomenally popular, routinely attracting 20,000 people when she appears with McCain, who struggles to draw a tenth as many on his own. Republicans in tight re-election battles, such as Senator John Sununu in New Hampshire and Senator Elizabeth Dole in North Carolina, say she improves their chances. Barack Obama's 8% lead among white women after the Democratic convention has become a 12% deficit, according to the latest Washington Post poll.

Will the bounce last? A number of Palin's statements have been shown to be half true at best, especially her repeated claim to have said "thanks, but no thanks" to the Alaskan bridge to nowhere.

Her support for it, now exposed in a video, a photograph and reams of local newspaper reporting, offers Democrats a line of attack. The defence she offered to Gibson was threadbare.

More than 37 million people watched her convention speech. In an election that Rick Davis frankly admits is "not about the issues" it will continue to define her.

The vice-presidential debate is a requirement, but those may be the only questions she answers between now and election day.