On February 23, a day after addressing America’s allies in Brussels, President George W. Bush will meet German Chancellor Gerhard Schroeder in the old city of Mainz on the Rhine. After the falling-out over Bush’s Iraq adventure, the two countries – so central to the transatlantic relationship in the past – are once again on speaking terms.

But, however welcome the return to cordiality may be, it is no more than that. If Bush and Schroeder are now showing the world how well they get along together, it is not because they are off to a new start, but because it suits their tactical interests. Had the American people chosen John F. Kerry over George W. Bush last November, the reunion would be seen by both sides as a new beginning, resonant with personal warmth. But both continue to doubt that past substantive divisions can really be overcome.

Thus, the meeting in Mainz will be one of those diplomatic courtesy calls that gloss over important bilateral differences. There will be no meeting of minds between Bush and Schroeder, because, on most key issues, their minds hold opposite views.

Consider what is potentially the most contentious issue, how to cope with Iran’s nuclear program. Germany has been determined, together with France and Britain, to get Iran to stop uranium enrichment through incentives and negotiation. While the US has now explicitly welcomed the European initiative, it remains openly skeptical and unwilling to join, thus weakening the chances of success. Failure would lead America to seek the UN Security Council’s formal condemnation of Iran, coupled with sanctions.

Indeed, the US is already trying to soften up Iranian resistance by hinting at a possible use of force. But there is no support in Europe for military action, and little backing for sanctions. If the negotiations should fail, the transatlantic cleavage could once again become glaringly wide.

The divisions are no less marked in another transatlantic quarrel, this one over whether to lift the European Union’s embargo on arms exports to China, imposed following the Tiananmen Square massacre 15 years ago. Schroeder has been pushing the EU to lift the embargo, a move that now appears imminent.

But for the US, the step is seen, not without reason, as an encouragement to China in its conflict with Taiwan. It will be interpreted as a stab in the back of US efforts to maintain stability in the region.

Nor will there be much progress on a matter dear to Berlin, namely Germany’s application to enter the UN Security Council as a permanent member. The prospect is uncertain enough as it stands that Bush may be spared the need to veto it. But it would make an immense difference for Germany’s chances if the US actively supported what is, after all, a reasonable objective of one of its most important allies.

But the Mainz meeting will not bring the two sides closer to working out a common position on any of these issues, or even to seeing the other side’s point of view. Instead, they will dwell on what is by now uncontroversial: welcoming the recent, if still fragile, progress in Israel-Palestine relations, supporting stability in post-election Iraq and Afghanistan, and extolling the transatlantic link.

The drafters of the farewell communiqué are, no doubt, already at work listing all the issues on which the two governments see eye to eye. Bush and Schroeder will make up for the paucity of substance with a good deal of friendly banter and bonhomie before the press assembled in Mainz.

That is, of course, better than nothing. But it amounts merely to a temporary papering over of differences, not their resolution. Worse, there is no sign that either man is willing to speak his mind in order to signal to the other side what he will expect when the next crisis looms. Future misunderstandings and misgivings are thus inevitable.

The welcome return to civility is not, therefore, a return to mutual trust. After all, the test of alliance does not lie in praising agreements, but in thrashing out disagreements in a spirit of cooperation. Neither Bush nor Schroeder seem ready for this.

If nothing else happens, the chief transatlantic partners will be no better prepared for the next crisis than they were for the last. As Leslie Gelb, the former president of The Council on Foreign Relations in New York, recently remarked, leaders in Europe and the US have lost the habit of serious cooperation.

What could revive that habit? Perhaps only a miracle: real progress in the Israel-Palestine conflict, which both the US and the Europeans could then claim to have helped bring about. Common success could make both sides realize that they still have a common cause.

But that miracle will not materialize in Mainz.