I have written about security and terrorism before (in The Guardian). One conference I went to a few years ago in Dublin involved sitting around working out how to hack into WiFi. ‘Black Hat’ security is about things like ‘reverse engineering’ software to work out how to break into it. It’s pretty useful both for governments and for companies to work out how secure their systems are. So I’m amazed this morning to find that a German hacker has been turned away from the US for carrying ‘training materials’ into the country. Here’s a guy who has actually trained US government officials about online security. But after a 9 hour flight and a 4.5 hour interview they sent him packing back home. There’s more on his blog here. Are we to take it that the US no longer wants to hear from people willing to educate its people? Roll on a new President…