Illustration by Jonathan McHugh / Ikon Images Like a toddler on a long drive, the UK bond markets are hot, grumpy and ready to puke. Gilt yields – the borrowing costs imposed by these markets – have reached feverish, multi-decade highs as ministers resign and MPs call on Keir Starmer to step down. Starmer’s supporters argue that this is precisely why you can’t get rid of him: he and his Chancellor, Rachel Reeves, have the backing of the market. BBC News is reporting that the investors who trade UK government debt are “unsettled” by the “perceived risk of looser public spending” that would result from a new, more left-wing Prime Minister.   This isn’t true. It serves an argument Starmer and Reeves have made repeatedly: depose us, and you’re in Liz Truss territory. But it’s a supposition, a crass generalisation of what thousands and thousands of people in different countries (and a whole bunch of algorithms) might think.…