France and Germany recently issued a joint postage stamp as part of a yearlong celebration of the 50th anniversary of the Elysee Treaty, the landmark agreement between the two former enemies.
The stamp is identical, except for one telling difference. In each country, it bears a picture of a man and woman, side by side, peering through lenses colored in blue-white-red and black-red-gold. But the French stamp costs 80 euro cents, while its German twin sells for only 75.
In a year loaded with symbolic gestures and 4,000 commemorative events, including Tuesday's joint session of Parliament, joint cabinet dinner and a concert, that 5-cent disparity is a reminder that despite the decades of friendship and enormous day-to-day cooperation, significant, often devilish, differences persist.
De Gaulle once described Europe as "a coach with horses, with Germany the horse and France the coachman." Since he signed the treaty with the German chancellor Konrad Adenauer in 1963, successive governments in both countries have struggled to overcome, or overlook, what divides them.
But the relationship has never been as close as some hoped. While the German news media celebrated Tuesday's anniversary of a treaty that has been a cornerstone for the European Union and German prosperity, the tone from France was harsher. Le Figaro called it "a friendship broken down," foundering on "diplomatic and economic tensions," while Le Monde called the event "a festival of hypocrisy."
The critical matter, however, is that war between the two peoples, who murdered one another for centuries, seems as inconceivable now as the Spanish Inquisition.
"Coming from a long history of conflict and war, they have succeeded in intertwining themselves so closely that today one can no longer imagine it any other way than both partners working closely together," said Georg Link, the German foreign minister's commissioner for Franco-German cooperation.
Chancellor Angela Merkel, a conservative, and President Franois Hollande, a Socialist, began the festivities on Monday here, with a question-and-answer session with university students from both countries. Sitting side by side, they appeared at ease for the first time since Mr. Hollande came to power last May, exchanging jokes and using first names — a public first, and a telling shift.
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Yet, even if the two succeed in establishing a better relationship, the tensions between centralized, statist France and federal Germany are real and will persist. They involve European issues like the euro zone crisis and the failed merger of the aerospace giants EADS and BAE Systems, as well as foreign policy matters, like the obvious disagreements over military engagements in Libya and now Mali.
French officials say the two leaders get on decently, agree on fundamental questions and maintain a daily web of contacts and relationships at all levels. They argue that former President Nicolas Sarkozy of France, a conservative, deferred too much to Ms. Merkel to the detriment of the euro and economic growth, and that Mr. Hollande and Ms. Merkel have gotten more done through compromise.
Honest about their differences, Mr. Hollande cited as examples of the new relationship a "pact for growth" to go alongside a fiscal discipline treaty, championed by Ms. Merkel, and the ability to come to agreement on the single banking supervisory system for the euro zone. Ms. Merkel said they planned to meet in May to work out a joint position on economic cooperation, growth and competitiveness ahead of the next European Union summit in June.
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The French have sought to "rebalance" the power structures within the European Union by working closely with the Spanish and Italian leaders, and softened the quasi-religious quality of the German prescription of budget discipline and debt reduction.
But it remains true in European Union affairs that Ms. Merkel's words carry more weight than those of any other leader — and not just because of Germany's demographic and economic power. There is an understanding that nothing works in the bloc without German agreement, and that France, weaker economically and more saddled with debt, plays a more junior role.
A survey of 25,000 people on either side of the border released ahead of Tuesday's festivities showed that while 80 percent of Germans and 70 percent of French hold the other in high regard, stereotypes persist.
The French still see themselves as Europe's center of policy creativity, but view Germany as the overly cautious, and increasingly begrudging, paymaster. The Germans, however, consider their caution one of their greatest assets, and grumble at French reluctance to overhaul their social welfare system and reduce their dependence on nuclear energy.
With an active military and a seat on the United Nations Security Council, the French also see themselves as playing a far more important diplomatic role globally, while Germany seems to have regressed in its willingness to use force.
As France has moved to engage militarily in Mali, for instance, responding quickly to help an ally, French officials note that while Britain was quick to offer air transport help, Berlin initially pledged only political support. The Germans have since offered two cargo planes.
On Tuesday the chancellor gave no indication of German eagerness to join the fight, thanking French troops for their efforts "for all of us."
One enduring bond between Paris and Berlin is a belief in the importance of the European Union as an anchor for peace and prosperity. The leaders have acknowledged that the strength of their bond has often proved troubling for their European partners, as seen in British efforts to renegotiate its terms for membership.
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"Europeans have a special view of German-French relations," Mr. Hollande told a group of students, with a smile. "When we get along, they are afraid it will be to their detriment. And when we do not get along, they realize then that it is to their detriment."