Trump looms large as Nato grapples with challenge of rearming Europe

Black-clad Turkish police on street corners, giant blue banners proclaiming "The Key to Peace" and a ceremonial welcome for Donald Trump. This may be a Nato summit but it's the US president who's had the metaphorical red carpet laid out for him.Trump has made no secret of his disdain for Nato. He says he has only come to Ankara this year because the summit is being hosted by his friend, the Turkish President Recep Tayyip Erdogan, who made a point of going to the airport to welcome Trump in person.Then the two men walked arm-in-arm while a band played the Stars and Stripes, and Turkish air force jets performed a flypast overhead, trailing red, white and blue smoke.There was always the risk that Trump would be something of a disruptor at this summit. And sure enough, his inflammatory words have punctuated the carefully crafted image of unity at this crucial gathering. Soon after landing, he delivered a throwaway line repeating that the US should really take over Greenland, an island that is part of the Kingdom of Denmark, a fellow Nato member.He did acknowledge, though, that his earlier thoughts on this subject had upset his relations with Nato. They certainly did. Denmark's prime minister has said if the US were ever to take Greenland by force it would spell the end for the alliance.