For me the alarm bells began to ring in the unlikely surroundings of the ancient Trout Inn near Oxford. A senior Republican party foreign affairs insider, as hawkish as they come and a staunch backer of the Iraq war, made a bitter complaint about the incompetence of George W Bush’s international policy. If my Republican friend is so critical, I thought, the US president must be in real trouble.

The seriousness of his difficulties is shown by the way in which the American administration is courting an unlikely stage army of salon revolutionaries who are promising to provide a painless way to get rid of the nasty regimes of the “axis of evil” in Iran and North Korea.

Peter Ackerman, the very rich chairman of Freedom House, and his International Center on Nonviolent Conflict are engaged in a huge propaganda campaign designed to show how the worst of regimes can be toppled by the methods used — or claimed to have been used — to overthrow Slobodan Milosevic in Serbia and in the “colour” revolutions that led to pro-western regimes in Ukraine (the orange revolution) and Georgia (the rose revolution).

Political street protests led by organisers trained secretly in the West and supplied with nifty communications gadgets are capable — so the argument goes — of ousting dictators.

But are conditions in Iran the same as those that followed the elections in Ukraine in 2004? Do street protests and similar techniques always work? The disastrous experiences of Tiananmen Square, of Prague in 1968 and Hungary in 1956 are conveniently overlooked. Nor does the State Department have many good ideas about how to spend the $75m recently allocated to promote democracy in Iran. The bulk of the money will be spent on radio broadcasts to be beamed into the country.

In the normal course of events it would not be worth considering the delusional arguments of Ackerman and his supporter Michael Ledeen, a journalist based at the American Enterprise Institute (AEI), who was a central figure in the notorious Iran contra affair during President Reagan’s administration. But President Bush and Paula Dobriansky, the undersecretary of state, have both addressed meetings organised by Ackerman’s Freedom House in the past two weeks. There are many other signs that the policy of promoting revolution and regime change in Tehran is gaining ground in Washington.

The US president is very much in a “last-chance saloon” mood as he made clear recently to the Hoover Institution at Stanford University. If he is to solve the problem of Iran’s nuclear ambitions he must achieve his objective before he leaves office in January 2009. So he is turning to a policy of subversion combined with plans for military action. There is convincing evidence that US diplomats are pressuring Turkish authorities to agree to the use of its main air base for attacks by American B-52 bombers on Iran’s nuclear facilities.

Since my time as an adviser to the policy planning staff of the Foreign and Commonwealth Office, and as a founder governor of the invaluable Westminster Foundation for Democracy (WFD), I have enjoyed close contact with Washington’s National Endowment for Democracy (NED). This body and other US organisations that promote democracy are worried that the secretive and subversive activities advocated by Ackerman, and being pressed for with some success on Capitol Hill, at the Pentagon and in the White House, will taint their past 20 years of international activity.

The projects of the NED — like those of the WFD — are funded by government but are transparent. They are not subversive. And they have played a positive role in encouraging democracy in dozens of nations. Respected members of the Iranian exile community in America are also worried that the attempted subversion of the regime in Tehran will backfire, consolidating support for Iranian hardliners and preventing regime change for the next 30 years.

Nevertheless, the seriousness of the underlying problem of nuclear proliferation cannot be denied. Nor will it be possible to negotiate successfully with regimes such as President Ahmadinejad’s unless there is a credible threat of the use of force. However long remains before Iran acquires a military nuclear capacity — itself a matter of uncertainty and misinformation — America and the West will need to decide whether they are prepared to tolerate an Iranian nuclear bomb and if they are willing to countenance the spread of such bombs to increasing numbers of unsavoury regimes.

Criticism of the Bush administration’s policy is not based on the fact that it is considering a military option against Iran. Any government needs to do this if it is to negotiate with Ahmadinejad

The problems are, first, that there seems to be no strategic thinking about the prospect of nuclear proliferation. Is it to be tackled by containment (as used against the Soviet Union and China in the cold war)? Or is it necessary to prevent proliferation, even if this requires military action as a last resort?

Second, the US administration lacks consistency. It has come to terms with the North Korean bomb. It is actively supporting India. It necessarily remains on good terms with Pakistan. Foreign policy obviously requires realism and pragmatism. It also requires some consistency of doctrine.

Third, Bush’s Washington still pays far too much heed to some of the wilder propagandists based in think tanks. Increasingly, bodies such as the AEI (for which I once wrote a scholarly volume on British political history) are less keen on sponsoring thinking and research. They are giving desk space and star roles to a breed of fast-talking practitioners of the television soundbite.

Finally, the Bush administration needs to ensure that the transparent, positive activities in the field of democracy promotion conducted in many countries by the NED and by a network of publicly funded bodies are not made casualties of the battle against nuclear proliferation.

Michael Pinto-Duschinsky is a director of the International Foundation for Election Systems in Washington

Andrew Sullivan is away