We've heard about how tourists are either boycotting holiday travel to the US, or are just scared by stories of people being detained for days or weeks on the border. But now it seems that even business travellers, who you would expect to be resistant to such issues, are also worried about, and increasingly avoiding, travel to Trump's America. And when they do go, they are taking the sort of precautions they previously only worried about if they were travelling to Communist China or Putin's Russia. Let's have a look.