AMBASSADORS tend to be men and women of tact and good manners. They follow a set of unwritten rules as they try to build relationships of mutual trust in order to represent their country’s interests effectively. Three guiding rules of the job are not to make headlines, not appear partisan, and never to lecture other governments on how to run their business. It took America’s new ambassador to Germany, Richard Grenell, less than two months to break all these rules.

Last week Mr Grenell, a loyal supporter of President Donald Trump, gave an interview to Breitbart, a far-right news site, in which he said he wanted to “empower” conservatives in Europe. “There are a lot of conservatives throughout Europe who have contacted me to say they are feeling there is a resurgence going on,” he said. “I absolutely want to empower other conservatives throughout Europe, other leaders. I think there is a groundswell of conservative policies that are taking hold because of the failed policies of the left.” He also described Germany's spending on NATO as "woeful" and criticised Angela Merkel, the German chancellor, for her immigration policies.

Mr Grenell’s pronouncements prompted scathing commentary on both sides of the Atlantic. “If the German ambassador in Washington were to say that I am here to strengthen the Democrats, he would be sacked immediately,” fumed Martin Schulz, the former boss of Germany’s centre-left Social Democrats, adding that the ambassador behaved like “far-right colonial officer”. Johannes Wadepfuhl, a deputy parliamentary leader of the centre-right (and generally pro-American) Christian Democrats, talked about an “unacceptable interference into our internal affairs". Sahra Wagenknecht, a leader of the far-left (and anti-American) Die Linke, demanded that the government “immediately expel” Mr Grenell. "He personally assured me that once he became Ambassador he would stay out of politics," tweeted Chris Murphy, a Democratic senator from Connecticut. "This interview is awful-Ambassadors aren't supposed to 'empower' any political party overseas".

It was not the first time Mr Grenell has upset his host country. On his first day on the job in May, he tweeted that German companies doing business in Iran should “wind down operations immediately” because American sanctions would target critical sectors of Iran’s economy. Germans were astonished and irritated by this. Wolfgang Ischinger, a former German ambassador to Washington, tweeted back: “Never tell the host country what to do, if you want to stay out of trouble".

Mr Grenell is ruffling feathers at a delicate time for the German-American relationship, which was exceptionally harmonious under President Barack Obama. Relations were strained by Mr Trump’s decision to pull out of the Paris climate accord and the Iran deal, and by his imposition of tariffs on imports of steel and aluminium from the European Union. Mr Trump has become hugely unpopular in a country once enamoured of America. Der Spiegel, a weekly, recently depicted Mr Trump on its cover as a blond-mopped, raised middle finger, accompanied by the words, “Goodbye, Europe!”. According to the centre-left magazine, Germany’s “relationship with the United States cannot currently be called a friendship and can hardly be referred to as a partnership. President Trump has adopted a tone that ignores 70 years of trust”. It concludes that “it is impossible to overstate what Trump has dismantled in the last 16 months".

Mr Grenell doesn’t seem to be the right man to repair any of this damage. A former contributor to Fox News, he was nominated by Mr Trump to be America’s next envoy to Germany in September. It took the Senate until April 26th to confirm Mr Grenell because of his history of making insulting comments to women. Asked about such these during his confirmation hearing, Mr Grenell claimed he was trying to be funny.

Germans are not amused by an ambassador. Mr Grenell insists that he has been misinterpreted. “Don’t put words in my mouth,” he tweeted. “The idea that I’d endorse candidates/parties is ridiculous. I stand by my comments that we are experiencing an awakening from the silent majority—those who reject the elites & their bubble. Led by Trump.” Like his master, Mr Grenell does not apologise, faults the “elites” and likes to communicate via Twitter. He has made himself even less popular with the German government by inviting Sebastian Kurz, the young Austrian chancellor whom he considers a “rock star” for lunch next week. Mr Kurz is another vocal critic of Mrs Merkel’s immigration policies.