THE drama roiling German politics lately had little to do with the bare facts. Notionally the dispute between Angela Merkel’s Christian Democratic Union (CDU) and the Christian Social Union (CSU), its more conservative Bavarian sister party, concerned asylum-seekers who are registered and meant to stay in other EU countries, especially Italy, but then travel to Germany. The number of such “secondary” arrivals so far this year is under 20,000: eminently manageable in a country of 83m. The subject did not even come up during coalition talks between the two parties (and the centre-left Social Democrats, or SPD) this spring.

Yet until July 2nd, when the CDU and CSU reached a shaky compromise, it seemed this modest subject could fracture that young government and even end Mrs Merkel’s long chancellorship—because for both sides it was the symbol of something larger. The CSUers were driven by years of frustration at what they deem the chancellor’s complacent and haughty leadership style, as well as blind panic at the rise of the anti-immigrant Alternative for Germany (AfD) in Bavaria ahead of a state election there in October.

For the chancellor their shibboleth, a demand that secondary migrants be checked and turned back at German borders, risked further undermining Europe’s battered “borderless” Schengen zone. That would weaken a multilateral international order which, with perhaps an eye on the history books, she considers it her job to help defend.

On June 18th the CSU leadership gave Horst Seehofer, the party’s boss, who is the federal interior minister, its blessing to implement the new border regime against Mrs Merkel’s wishes, while first granting the chancellor two weeks to pursue an alternative “European solution”. On July 1st she reported back on an EU-wide agreement to tighten Europe’s external frontiers. She outlined deals with 14 individual states whereby these would readmit secondary migrants from Germany. At a fraught eight-hour meeting in Munich the CSUers deemed the package inadequate. Mr Seehofer resigned rather than defy the chancellor, but then at the urging of his colleagues unresigned, pending one final meeting with her. Late the next day, amid speculation that the CSU could quit the coalition, the two sides finally reached a deal.

It pledges new controls on the Austrian-German border, the main entry point for immigrants travelling from Europe’s south (see map); extraterritorial “transit centres” on borders from which rejected asylum-seekers will be deported to countries with bilateral deals with Germany; and a policy of turning back those whose countries of registration do not have such a deal, under an arrangement to be agreed with Austria. Mr Seehofer got a crackdown that will play well in his home state in the run-up to the election there; almost the entire border that Germany shares with Austria is Bavarian. So Mrs Merkel managed both to resolve the dispute and to avoid unilateral German action.

Neither of her achievements looks firm, however. Settling the battle with the CSU may now cause one with the SPD, which opposes any measures that would formally detain asylum-seekers. A meeting of the three party leaderships on July 3rd produced no agreement.

In any case, is the CDU-CSU conflict really settled? Only hours before the deal was struck Mr Seehofer was seething contemptuously: “I won’t be dismissed by a chancellor who is only chancellor because of me.” Having achieved concessions by pushing Mrs Merkel to the brink this time, his party will be tempted to do so again—whether on immigration or another subject, like euro-zone reform.

Meanwhile the agreement will avoid unilateral German action only if the right international deals can be done in the coming weeks: most notably a repatriation arrangement with Italy, whose new populist-led government says it wants fewer, not more, asylum-seekers on its territory; and a border deal with Austria, where politics has taken an anti-immigrant turn since the refugee crisis and where the hard-right Freedom Party controls the interior ministry. In a frosty statement issued on July 3rd the government in Vienna, where officials bridled at Berlin’s failure to consult them, threatened to impose new controls on its own southern border if the Germans started turning back asylum-seekers. That jeopardises the smooth flow of people and goods over crucial transalpine routes such as the Brenner Pass.

In other words, the deal in Berlin may not pacify the CSU and risks unleashing precisely the domino effect of unilateral actions that Mrs Merkel most feared. Rather than averting the choice between her domestic political interests and those of the wider European order, she may have merely postponed it.