It may seem incredible to say this, given past experience, but a few years from now Europe and the world could be looking back at the Bush administration with nostalgia. This possibility will arise if the US elects Senator John McCain as president in November.

Over the years the US has inserted itself into potential flashpoints in different parts of the world. The Republican party is now about to put forward a natural incendiary as the man to deal with those flashpoints.

The problem that Mr McCain poses stems from his ideology, his policies and above all his personality. His ideology, like that of his chief advisers, is neo-conservative. In the past, Mr McCain was considered to be an old-style conservative realist. Today, the role of the realists on his team is merely decorative.

Driven in part by his intense commitment to the Iraq war, Mr McCain has relied more on neo-conservatives such as his close friend William Kristol, the Weekly Standard editor. His chief foreign policy advisor is Randy Scheunemann, another leading neo-conservative and a founder of the Committee for the Liberation of Iraq. Mr McCain shares their belief in what Mr Kristol has called "national greatness conservatism". In 1999, Mr McCain declared: "The US is the indispensable nation because we have proven to be the greatest force for good in human history... We have every intention of continuing to use our primacy in world affairs for humanity's benefit."

Mr McCain's promises, during last week's visit to London, to listen more to America's European allies, need to be taken with a giant pinch of salt. There is, in fact, no evidence that he would be prepared to alter any important US policy at Europe's request.

Reflecting the neo-conservative programme of spreading democracy by force, Mr McCain declared in 2000: "I'd institute a policy that I call ‘rogue state rollback'. I would arm, train, equip, both from without and from within, forces that would eventually overthrow the governments and install free and democratically elected governments." Mr McCain advocates attacking Iran if necessary in order to prevent it developing nuclear weapons, and last year was filmed singing "Bomb, bomb Iran" to the tune of the Beach Boys' "Barbara Ann".

Mr McCain suffers from more than the usual degree of US establishment hatred of Russia, coupled with a particular degree of sympathy for Georgia and the restoration of Georgian rule over Abkhazia and South Ossetia. He advocates the expulsion of Russia from the Group of Eight leading industrialised nations and, like Mr Scheunemann, is a strong supporter of early Nato membership for Georgia and Ukraine. Mr Scheunemann has accused even Condoleezza Rice, secretary of state, of "appeasement" of Russia. Nato expansion exemplifies the potential of a McCain presidency. Apart from the threat of Russian reprisals, if the Georgians thought that in a war they could rely on US support, they might be tempted to start one. A McCain presidency would give them good reason to have faith in US support.

Mr McCain's policies would not be so worrying were it not for his notorious quickness to fury in the face of perceived insults to himself or his country. Even Thad Cochran, a fellow Republican senator, has said: "I certainly know no other president since I've been here who's had a temperament like that."

For all his bellicosity, President George W. Bush has known how to deal cautiously and diplomatically with China and even Russia. Could we rely on Mr McCain to do the same?

Mr McCain exemplifies "Jacksonian nationalism" -- after Andrew Jackson, the 19th-century Indian-fighter and president -- and the Scots-Irish military tradition from which both men sprung. As Mr McCain's superb courage in North Vietnamese captivity and his honourable opposition to torture by US forces demonstrate, he also possesses the virtues of that tradition. Then again, some of the greatest catastrophes of the 20th century were caused by brave, honourable men with a passionate sense of national mission.

Not just US voters, but European governments, should use the next nine months to ponder the consequences if Mr McCain is elected and how they could either prevent a McCain administration from pursuing pyromaniac policies or, if necessary, protect Europe from the ensuing conflagrations

Anatol Lieven teaches at King's College London and is a senior fellow at the New America Foundation in Washington, DC.

This article originally appeared on the Financial Times, and is published here by kind permission of the author.