Neil Armstrong, who is American man, was the first person landing on the moon in 1969. He put up the U.S flag on the moon when he made his first step on it to show achievement and pride which are for not only him, but also all American citizens. Surprisingly, besides just in order to be used to display in the air, a national flag is a symbol to represent a country and a nation. It has the strongest potential to stir up emotional responses among other symbols of a country. It can lead people have willing to sacrifice their lives to it, or push people to burn it whenever having protest. Therefore, national flag is a really powerful symbol and people should respect it. A national flag is symbol indicating priceless history and ideal of a country