In the lead-up to President Bush's European tour this week, there has been feverish speculation in London that the leader of the free world will voice his support for the European Constitution while in Brussels. Rumours have abounded that the White House, under sustained pressure from the European Union (EU), is about to cave in to Franco-German demands that Washington back the drive for a more united Europe in return for European support over Iraq, Iran and the war on terror.

The rumour-mill was given added strength by the US's new Secretary of State Condoleezza Rice's support for a "unified" Europe - with a single EU foreign minister - in an interview last week with the Financial Times. Rice's remarks have been widely reported in European media as an official endorsement by the Bush administration of the EU Constitution and a common foreign and security policy (CFSP). While they are a reflection of conventional wisdom in the State Department, which has traditionally adopted a pro-European outlook, they should not be viewed as the dominant position in the executive branch of the US government.

In fact, there is a healthy debate currently taking place within the administration over the future direction of Europe, the Pentagon and the White House adopting largely sceptical positions on the question of further European integration. Significantly, Secretary of Defence Donald Rumsfeld last week pointedly refused to endorse the idea of further political integration in Europe.

The notion of President Bush, the most Euro-sceptic American leader in a generation, supporting the EU Constitution and the concept of "ever-closer union" in Europe, is a pipe-dream conjured in part by powerless Washington liberals whose leader was decisively defeated last November. The comment and analysis pages of America's establishment papers have been filled in recent days by Democrat-leaning commentators calling on Bush to embrace the move toward greater European integration in a renewed spirit of harmony and reconciliation as he makes his way across the Atlantic.

Had presidential challenger John Kerry, and not George Bush, won the 2004 election, not only would the US president be backing a federal Europe, but France and Germany would also have been elevated to the status of Britain in terms of importance to the United States. As it stands, the UK remains America's closest ally and the White House has little time for President Jacques Chirac's delusional dreams of building a counterweight to American global power.

While the EU Constitution, with its 300 pages of almost impenetrable tedium, is hardly bedtime reading in the West Wing, strategists in Washington are increasingly aware of the dangers it poses to long-term US strategic interests. For instance, they have taken note of Article I-16 of the Constitution, which states unequivocally: "Member States shall actively and unreservedly support the Union's common foreign and security policy in a spirit of loyalty and mutual solidarity and shall comply with the Union's action in this area."

An artificially-unified European foreign policy would in many ways be a nightmare scenario for planners in Washington, making a "coalitions of the willing" strategy impossible to operate. For example, if a common European foreign and security policy had genuinely functioned in 2003, Belgium, France or Greece (all states with strongly anti-American publics) could have vetoed the UK, Poland, and Italy from aiding the United States in Iraq.

The most prominent major casualty of a CFSP would be the Anglo-American special relationship, forcibly consigned to the scrapheap of history. America's closest ally in the war on terrorism would be unable to operate its own foreign policy and stand alongside America when and where it chose to do so. A neutralised Britain would be forced to remain on the sidelines while America confronted rogue states such as Iran, North Korea and Syria. The consequences for American foreign policy would be hugely damaging. It is highly conceivable that in such circumstances, the United States would have to wage its next major war on its own, with no significant military ally present.

The president's advisers are acutely aware that any endorsement by Bush of the European Constitution will greatly undermine the efforts of those campaigning against ratification of the constitution in Britain and other European countries, such as Poland and the Czech Republic. If the United States were to give its backing to Franco-German efforts to forge a united Europe, supporters of the European Constitution would use it to their advantage in referendum campaigns, painting their opponents as hopelessly isolated on the international stage. Supporters of the European Constitution in Paris, Brussels and Berlin, who include many of President Bush's fiercest international critics, would be clearly delighted by the prospect of the world's only superpower singing to their tune.

The White House is closely following the polls in London, which show that an overwhelming majority of Britons are opposed to the EU constitution. It is aware that a British rejection of the EU Constitution will scupper the plans of the Euro-federalists to create a Europe-wide superstate. The end result is likely to be a multi-speed Europe, based on the principle of each individual state having greater choice about its level of integration with Brussels. A more flexible Europe perfectly suits President Bush's global vision, outlined in his recent State of the Union address, of "a community of free and independent nations, with governments that answer to their citizens, and reflect their own cultures". Such an outcome would clearly be in America's national interest, which is why the American president won't be backing a federal Europe any time soon.

Once Britain votes "no" to the European Constitution, it will be in Britain's, Europe's and America's interests for that vote to spark a fundamental rethink about the European project. Britain and the other non-euro countries would ideally withdraw from the customs union and single market regulatory structure and instead negotiate free-trade deals with the euro core and with America. That is the way to further free trade and to raise European living standards.

This new grouping could also work with America and other allies to strengthen military co-operation, raise defence expenditure and build the institutions that we will need for the next few decades. A recent poll for the New Frontiers Foundation, conducted amid the worst news from Iraq, showed strong public support for this agenda over the option of the euro and further integration. This is the future that conservatives in America and Britain should be building.

Nile Gardiner, Ph.D., is a fellow in Anglo-American security policy at The Heritage Foundation.

John Hulsman is research fellow in European affairs at the Heritage Foundation.