TURKISH membership of the European Union is set to acquire an irresistible momentum after yesterday’s vote by the Commission to recommend the opening of accession talks. For many Europeans, from the highest government leaders to the lowliest unemployed citizens, this will come as a great shock. The widespread opposition to Turkish membership is not just a symptom of racial and religious prejudice.

There are serious costs to admitting a country with a population nearly as big as Germany’s, but an income per head little more than half of Poland’s. There are natural concerns about where to “draw the line” on future EU enlargements. There are also perfectly legitimate worries about embracing a country that has already suffered from Islamist terrorism and extending Europe’s borders to the most volatile parts of the Middle East.

Such reasonable arguments are unlikely to prevail, however, for at least three reasons. First, Turkish membership will make even more unattainable the dream of a federal European state, for which public support has been dissipated by the Continent’s economic and political failures. Secondly, the opponents of Turkish membership have made the mistake of presenting their objections using religious and cultural rhetoric. Thirdly, and most importantly, all the worries about Turkish membership are trumped by the geopolitical pressures connected with the war on terrorism.

The first point, about the loss of faith in “ever-closer union” speaks for itself. What is less obvious is that hostility to centralisation could translate into positive support for Turkey among the millions of EU citizens who will see it as the ultimate insurance policy against federalist ambitions in Brussels.

An example of this dynamic is the way that Turkey is likely to scupper the strongest argument in favour of ratifying the European constitution: the claim that voting rights among the EU member nations must be reformed to accommodate past and future enlargements. The fact is that, far from preparing the EU for the future, the constitution will have to be torn up if Turkey joins. Turkey’s rapidly growing population, which will overtake Germany’s by 2015, would give it more votes under the new constitution than any other nation. Since an EU with Turkey as the single most powerful member would make no sense to anyone, including even the Turks, enlargement would mean completely rewriting the constitution just five years after the new arrangements are supposed to come into force. While conspiracy theorists suspect that the constitution was drafted to block Turkey’s accession, it looks increasingly like Turkey will sabotage the new constitution.

Turning to religious and social issues, the outrage over Turkey’s proposal to criminalise adultery (now hastily withdrawn) should be seen in the context of the religiously-inspired laws that have been on the statute books of many EU countries. In Italy, divorce was illegal for decades after it joined the EU, while in Ireland abortion was outlawed until 1992. Against that background, the righteous indignation about Turkey’s conservative social norms looks distinctly hypocritical.

The real objection to Turkish membership is certainly related to religion, but not in the way suggested by the country’s opponents. The threat from Turkey lies not in the growing influence of Islam, but of Islamic radicalism — specifically the militant Wahhabi. It has been said that more mosques have been built in Turkey during the past decade than in the whole of the country’s previous history. Many of these have been financed by Saudi money and dedicated to the Wahhabi creed. If this missionary campaign continues, then Turkey will become a gateway into Europe not just for moderate Muslims, who should be no more difficult to assimilate than any other religious group, but for fanatical Wahhabis who will, in turn, try to infect other Muslims across Europe with their intolerant faith.

But if the threat to Europe is the spread of radical Islamic thought, then the best way to stop this infection is to isolate its intellectual and financial origins in Saudi Arabia. If the Turks had better secular education and more incentives to lead secular modern lives, they would be less susceptible to fundamentalist mosques.

This is, of course, the strongest argument for drawing Turkey into Europe. Far more than Iraq, a tolerant and democratic Turkey really could become a beacon of hope for rational, moderate Muslims around the world.

There is, however, a peril lurking behind this idealistic case for bringing Turkey into Europe — and it is this that, I suspect, motivates the strongest fears about bringing Turkey into the EU. Suppose that Europe succeeded in offering the Turks a secular model of social and economic development. And suppose that the hopes of a more prosperous secular life rippled out into other Muslim countries on Europe’s periphery: Morocco, Tunisia, Algeria, Libya, even Egypt. Would this really make Europe safer?

In the long run, it certainly would. Making Turkey and ultimately the whole Mediterranean basin more European offers the best hope of reversing the spread of militant Islam and averting a global war of religion.

In the short-term, however, a great danger goes with this hope. For would not the successful assimilation of Turkish Muslims into European secular civilisation pose the ultimate challenge to the fundamentalist fantasy of a new Caliphate to rule over a reunited Muslim world? Would not the assimilation of the Muslim Mediterranean heartland into a secular Europe be an even greater provocation than the influence of American culture in Saudi Arabia to fanatics such as Osama bin Laden, who still laments the “tragedy of Andalusia” and dreams of reinstating Muslim sovereignty in Spain?

With Turkey now on Europe’s doorstep, we are destined to find out.

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