(Bloomberg Opinion) -- It was just weeks ago that German Interior Minister Horst Seehofer, who is also leader of Bavaria’s Christian Social Union party, appeared to have the power to end Chancellor Angela Merkel’s political career. Now he’s beleaguered, and his party’s support is at a historic low. Adopting a tactic that has worked for other center-right parties in Europe – embracing anti-immigrant slogans to keep voters from defecting to the far right – has proved a disaster for Seehofer.

The CSU, which has ruled Bavaria, Germany’s third richest and second most populous state, since the first post-war years, enjoys an absolute majority in the state parliament. It risks losing it in October. So Seehofer bet on an anti-immigrant push ahead of the election.

Last month, Seehofer threatened to use his ministerial powers to start pushing asylum seekers registered in other EU countries back from the German border, should they try to cross it. Though there are, at most, 1,000 such travelers per month, CSU leaders  apparently thought Bavarians would appreciate the party’s determination to protect the border. The state, after all, lay on the path of most refugees crossing into Germany in 2015 and 2016, when Merkel let them come in without much hindrance. After all, stealing some of the far-right’s thunder worked well for established center-right parties in the the Netherlands and Austria.

The gambit didn’t work out, though. Threatened with the breakup of the governing coalition and, perhaps even worse, the CDU-CSU alliance, formed in 1949, Merkel went to work negotiating common immigration policy moves with other EU leaders and making Seehofer’s unilateral stance look unreasonable. Seehofer threatened to resign – but instead struck a largely unworkable compromise with Merkel. Under the deal, “secondary migrants” whom the CSU called “asylum tourists” are to be held in custody in Germany before they can be sent to the countries where they are registered – with those countries’ consent, of course, to be negotiated with each EU member state separately.

Seehofer must have realized the deal was problematic. Italy, for example, has been trying to get other EU nations to help in relieving its disproportionate refugee burden, so it it’s unwilling simply to have people pushed back at it. But refusing to bend threatened to do more harm than good – at worst, it could have forced a national election with the CDU competing against the CSU in Bavaria, a nightmare scenario for the local conservatives.

Since making the deal with Merkel, Seehofer’s luck turned subtly for the worse.

As he presented his ministry’s plan to get immigration under control, he boasted that 69 failed asylum seekers had been deported to Afghanistan on his own 69th birthday, July 4 – the timing was purely coincidental, he winked at reporters. A few days later, it transpired that one of the returnees, a 23-year-old man, committed suicide upon arrival in Kabul. A political uproar followed and Seehofer’s semi-apologies failed to stem it.

Seehofer has also faced sharp criticism for threatening reprisals against the crew of the ship Lifeline, owned by the eponymous German nonprofit, which has been picking up migrants in the Mediterranean to save them from drowning and bringing them to European ports. The ship’s captain recently called Seehofer a criminal and called for his resignation.

And then there’s the case of Sami A., not identified by his full name under Germany’s privacy laws. The 42-year-old, who came to Germany in 1997, stands accused of having served as a bodyguard for Osama bin Laden. In June, he was deported to his native Tunisia despite being married to a German citizen, with whom he has four children – just as Seehofer had promised he would be, back in May. Last week, a court in Duesseldorf ruled, however, that Germany was to bring Sami A. back because there was no guarantee he would be treated humanely in Tunisia, where he’s accused of terrorism. Though there’s not much sympathy for Sami A. himself, the case helped forcus the public’s attention on Seehofer’s deportation practices, lending them a flavor of arbitrariness.

None of this is good for the leader of a Christian party, who is supposed to show some charity, not just toughness. Cardinal Reinhard Marx, the archbishop of Munich and chairman of the German Bishops’ Conference, has criticized Seehofer and Soeder for their harsh words about asylum seekers. “To say we should all shift right because the spirit of the time is shifting right is the wrong idea,” he told the weekly Die Zeit. “A party that decided to put that C in its name has a certain obligation in terms of the Christian social teaching concerning the poor and the weak.”

“Everyone who wants to see it see that there’s a campaign being conducted here against me and my party,” Seehofer complained in an interview. He admitted, though, that even some people inside the CSU are unhappy about what’s going on.

That’s hardly surprising. The CSU, which routinely got 49 percent support in 2014 and managed more than 40 percent early this year, has dropped to 38 percent in the latest poll done by Infratest dimap for the Bavarian Radio – the lowest ever for the party that has come to be synonymous with Bavaria. It’s not the far-right Alternative for Germany (AfD) that’s driving down the CSU’s support: The AfD stands at 12 percent in the Bavarian Radio poll, exactly where it was in April when the CSU reached 41 percent.

Shifting to the right to cover that flank sounded like a good tactic, but with Merkel’s quiet, behind the scenes magic working against Seehofer as it has worked against many previous challengers to her authority, it has backfired. Merkel’s line – that the center-right should take on parties like the AfD head-on from a liberal, relatively compassionate position – still works well with Christian voters and moderates in general, especially as they watch Donald Trump’s antics in the U.S. 

Seehofer should have listened to CSU general secretary Markus Blume, who earlier this year proposed attacking the AfD with all of the CSU’s might rather than pandering to its supporters. It may be too late for an about-face, but it’s not too late for a lesson.

To contact the author of this story: Leonid Bershidsky at lbershidsky@bloomberg.net

To contact the editor responsible for this story: Therese Raphael at traphael4@bloomberg.net

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.

Leonid Bershidsky is a Bloomberg Opinion columnist covering European politics and business. He was the founding editor of the Russian business daily Vedomosti and founded the opinion website Slon.ru.

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