The king of Denmark has asked a centre-right politician to try to form a new government after the prime minister, Mette Frederiksen, has failed to put together a ruling coalition. The announcement on Friday night shook the political establishment as Frederiksen has been a staple of Danish politics for decades. Her left-leaning party, the Social Democrats, won the plurality of votes in parliamentary elections in March. But despite winning the most votes, it was the Social Democrats’ worst electoral showing since 1903 and no party won a majority. Frederiksen has since tried to form a left-leaning government with the support of Lars Løkke Rasmussen’s centre-right moderates. He is seen as a kingmaker owing to his position in the middle between Frederiksen and Troels Lund Poulsen, the chair of the centre-right liberal party. Troels Lund Poulsen (L), the then defence minister, with Mette Frederiksen in September.…