I'd explain both sides- and that neither are right. It's an opportunity to help teach him possibly about how to draw his own conclusions, when presented with all sides of an issue. I remember vividly my parents doing the same with me when it came to nuclear weapons (I was the only five year old who could tell you what Hiroshima was and why it was bad- hippy parents), the situation in Rwanda in 1994, apartheid, etc etc. THe fact is this country DOES have a huge slant, and i think it's important for anyone, kid or adult, to think critically about things.