Kyoto was "blocked by pressure from the polluters."

Gore added that Exxon-Mobil and other big companies

"purposely confused people" with tens of

millions of dollars of advertising and lobbying

that disparaged the science behind global warming

Gore: Agitator & Propagandist

There is less news than meets the eye in Barack Obama's reported offer of a cabinet position for Al Gore.

For one thing, Obama made much the same gesture months ago, telling Time magazine that he would welcome the former vice-president as a member of his cabinet.

But, as Obama surely knows, it ain't gonna happen. Gore has said so publicly, telling Time in a separate interview that he is not interested in serving in the next president's cabinet, whoever that president is. Gore has been similarly categorical in ruling out running for president again.

On one level, it's easy to see why Gore doesn't want to get back into the White House.

After winning a Nobel Peace Prize and an Oscar for his climate change evangelism, he has attained global rock star status and now enjoys far more political influence than most cabinet members do.

As such, he is certain to be closely consulted about climate change policy by the next president, especially if that president is Obama or Hillary Clinton.

But Gore has deeper reasons for staying out of the Washington whirl - reasons that deserve our attention, for they suggest the kind of battles that must be fought and won in Washington if catastrophic climate change is to be avoided.

Pundits find it hard to believe that a lifelong politician could turn his back on the White House.

But as someone who has been covering Gore's climate activism for 15 years now, I believe that it is precisely what Gore learned while serving in the White House under Bill Clinton that is now leading him to follow a different path.

I spent two hours one-on-one with Gore just before An Inconvenient Truth was released.

Much of the interview focused on an irony that seems to have escaped many of those who have urged him to run for president: the last time he was in power, he failed to deliver much progress against global warming.

During its eight years in office, the Clinton-Gore administration did not pass a single major law against climate change.

It did sign the Kyoto Protocol, but only after watering it down with crippling loopholes, and then it chose not to seek Senate ratification of the treaty.

In our interview, Gore acknowledged these failings. But he argued that the blame lay not with him or Clinton, who, he said, "was much more responsive than not".

Rather, Gore said, "the resistance was tremendous" from the status quo. The two richest, most powerful industries in American history, oil and autos, were fiercely opposed to cutting emissions, as were coal and electricity companies.

Kyoto was "blocked by pressure from the polluters," Gore told me, adding that Exxon-Mobil and other big companies "purposely confused people" with tens of millions of dollars of advertising and lobbying that misrepresented and disparaged the science behind global warming.

This disinformation campaign encouraged "massive denial in the country as a whole" and "conditioned the battlefield" in Washington so that Congress ended up blocking reform.

The lesson Gore seems to have drawn from his defeats is that being president is not enough to create real change, especially if powerful interests are against you.

The only way to defeat those interests is to "re-condition the battlefield", as Gore put it - to build such a pervasive wave of public pressure that no matter which politicians get elected, they will feel compelled to take action, even if it means disappointing Exxon-Mobil and friends.

That's what happened when public opinion, activism and protests led President Lyndon Johnson to sign a 1964 Civil Rights Act that was very similar to the bill he and most members of Congress had voted against in 1958.

It's what happened when President Richard Nixon finally removed US forces from Vietnam, even though privately Nixon wanted to persevere and win.

Gore's years in the Clinton White House appear to have taught him a vital lesson about modern democracy, a lesson that is omitted from most textbooks and news coverage: being president, like being right, is not enough.

The only way to beat organised money is with organised people, lots of them. Gore is now helping to build that grassroots pressure, even though it means giving up on the presidential dream he has harboured since childhood.

As much as any specific policy advice he might give president Obama, it is this energised public opinion that will do the most to help save the US and the world from the climate change catastrophe that threatens to engulf us.