LONDON-As fighting rages in Fallujah and Najaf, and as John Kerry explains that he threw his ribbons but not his medals over the wall in 1971, other things are happening that will shape the world and America's place in it for years to come. Consider the continuing struggle between Old Europe and New Europe. Old Europe--the term was popularized by Donald Rumsfeld in January 2003--is composed of the core nations of France and Germany and their poodle Belgium, the historic heart of the European Union. Old Europe opposed military action in Iraq and, in EUaffairs, is striving to create a unitary, France-like Europe--with an expensive welfare state and insulation from competition. Old Europe wants to be a counterweight to the United States economically and in foreign and military affairs.

New Europe is not so cohesive or purposeful. On Iraq, the United States had the support of most European governments--Britain, Italy, Spain (which switched after its March 14 election), the Netherlands, Denmark, Poland, the Czech Republic, and others. But on economics, there has been no such unity. Poland, the Czech Republic, and the eight other accession states that officially joined the EU on Saturday wanted to be in the trade bloc despite qualms about its statism. Italy, happy to ditch the lira for the euro, has long loved the EU. Britain, with a freer and more vigorous economy than Old Europe, does not want to be strangled by overregulation and rigid labor laws.

The great project of Old Europe has been the EU constitution, drafted by a convention that was presided over by former French president Valery Giscard d'Estaing, which would create a single entity of Europe with an executive and a foreign ministry. Last winter that seemed blocked by Spain and Poland, which demanded greater representation. But the new Spanish government announced it was joining Old Europe and dropped its objections, and Poland acquiesced as well. Suddenly, it looked as if the EUconstitution would go through. Further negotiations were scheduled for June, and agreement was expected (after the long European summer vacation) by fall.

Then on April 20 Tony Blair rose in the House of Commons and made a U-turn. For months, he had refused a referendum on the EU constitution; now he promised to hold one, but only after parliamentary deliberation--probably not until the British general election he is expected to call in May or June 2005. It was an uncharacteristically clumsy move: Blair gave varying answers on what would happen if Britons voted no. Politically, Blair may have robbed the Conservatives of an issue in the June election for the European Parliament and Britain's general election next year. But Blair's U-turn also added to his reputation for slipperiness and spin, which grew amid the controversy over the "dodgy dossier" supporting the war and the suicide of weapons inspector David Kelly last July. An investigation exonerated Blair and his government in the Kelly affair, but polls showed most voters did not agree.

"Red lines." On the EU constitution as well, Blair does not have public opinion on his side: A recent poll showed 16 percent in favor and 53 percent opposed. Opponents argue that it would create a European superstate and transfer power from elected British officials to unelected EU bureaucrats. Blair says that in the June negotiations he will insist on "red lines" maintaining British sovereignty on foreign and macroeconomic policy, and argues that only by accepting the constitution can Britain influence the direction of Europe. In other words, he wants Britain to approve the constitution so he can fight to make Europe less Old and more New.