Gen Sir Richard Shirreff says US president has launched war of choice in Iran with no clear grasp of how it will end

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Britain cannot become embroiled in a war “without a clear end point”, a former senior Nato commander has said, as he defended Keir Starmer after Donald Trump’s jibes that he was “not Winston Churchill”.

Trump was “another American president who had launched a war of choice,” said Gen Sir Richard Shirreff, as a minister insisted that the UK prime minister had acted “with a cool head” by not allowing British bases to be used for initial strikes.