US President George Bush todays welcomes German Chancellor Angela Merkel to his Texas ranch at the beginning of a two-day visit. It's a privilege that's only extended to world leaders who George Bush views as close allies. But there's a paradox here because although the US president clearly views the woman he calls "Angie" as very much a buddy there are serious and substantive differences between the two -- not least on the issues of Iran and Afghanistan. Let's take a closer look at the agenda for the meeting.