I agree with Evilqueen (regardless of whether he said it or not.), that he should have some foreknowledge about the culture or group of people he is to address, but that lack of knowledge cannot necessarily be blamed on him. I'm willing to bet that (assuming this did happen.) he has a team of researchers and diplomacy experts who coach him on the culture's characteristics and what he should and shouldn't say. In a scenario like this, that team would be to blame, not the Commander in Chief. There aren't enough hours in the day for the man to learn everything there is to know about a culture. He's got enough on his plate. That's why he's got as many assistants as he does. Know the chain of command, because when things go awry, the sh*t always rolls down-hill. Heck, maybe he did put a large amount of time into studying this culture. I mean, ya don't want to walk blindfolded into a mine-field, but at the same time, mines are still there, and ya can still get blown-up. Anyone can make a mistake, but when you're under the microscope, people begin to change their image of you. The man just happens to be under one of the world's largest microscopes.