I think the key is to educate, not defend.
I was once asked why Chinese women like to use umbrella under the sun? Why does China build artifical islands in South China Sea? Why does China support North Korea? Why does China kill prisoners to get organs? and on and on.
Most of americans don't care about what happens in other countries, TV news is a very good example. Many knowledges got are from very limited sources. So education is a key.
For example, I said Chinese women like to use umbrella becasue they don't want to darken their skin. In our culture white skin has been regarded as a very important trait that shows this person is from an upper-class or wealthy family, well-educated and enjoy a comfortable lifestyle indoors, and bla bla bla.
For atrifical islands, I told them about the history that the area used to belong to China for thousands years, until after 1949, Taiwan was taken over by the Nationality party. Other countries tried to take advantage of China during the civil war and the culture revolution, but in Chinese eyes, it always belongs to China. And bla bla bal.
For North Korea, we talked about what would happend if in war, the refugees, the relations between three generations of power, how North Korean perceives after the Knrean war, how Gaddafi's fate compared to Kim, how China trys its best, and how the reaction of US to Cuba missile crisis. bla bla bla.
And I've found, most of Americans would accept your explanations, and next time when they have problems, they will come back to ask you again.
So do prepare yourself.
