“We’ve had some very bad allies in Nato,” US President Donald Trump said on Wednesday, warning Washington could walk away from the transatlantic alliance unless allies fall in line with his Iran policy. Nato Secretary General Mark Rutte plans to visit the United States soon to stabilise the alliance.The timing is stark: Trump’s latest threat comes as several European capitals have openly refused to back Washington’s campaign to unblock the Strait of Hormuz, with some blocking the US from using...