For more than four decades, European leaders have held out to Turkey the prospect of membership in their club. The odds that Turkey would join Europe shortened considerably last week, when officials from the European Union and Ankara agreed to commence discussions on Turkish membership next October. Membership is not a done deal, however. Turkey must continue its reforms and close the social and ideological gaps that separate it from Europe.

Most important, it must win over European public opinion and allay concerns about the impact of Turkish membership on the EU. Success will pay dividends far beyond those felt in the states most immediately affected: Turkey's accession to the EU will help silence those who claim there is a "clash of civilizations" between the Western and Muslim worlds.

Turkey straddles two worlds. It is situated on the southeastern reaches of Europe, it borders the Middle East, and it possesses a predominately Muslim population. It has been an associate member of the EU for 40 years and a member of the North Atlantic Treaty Organization still longer. Yet previous efforts to join the EU ended in failure. The primary objection was that the country's authoritarian politics could not be accommodated by Europe's liberal democratic framework, although the objections of Greece -- Turkey's longtime rival -- contributed to the problem. Nonetheless, the door was never closed -- if nothing else, to encourage continuing evolution in the right direction.