The attack on Sep. 11, deemed as the first foreign attack on U.S. soil since the bombing of Pearl Harbor at the beginning of World War II, destroyed the World Trade Center Towers in New York City, damaged the Pentagon in Washington, and crashed a passenger airliner into the Pennsylvania countryside, claimed more than 5,000 lives, caused a nationwide panic and kicked off a worldwide battle against terrorism. The Americans quickly recover from the begining panic, and unite around their government to fight with the disaster they had never faced with before. Usually, the national flag of the United States of America is a potent symbol of unity in times of war and crisis. In this situation, most Americans ask for a postage stamp bearing the star-and-stripe flag for their use in the everyday mail. USPS responsed to the desire, designd and issued the new "United We Stand" flag stamp in the soonest time.

The new stamp, issued in self-adhesive convertible pane of 20 and coil of 100, has its first day on Oct. 24 in Washington, D.C., and throughout the states of New York, Pennsylvania and New Jersey, which are the places reflecting the sites of the 9-11 terrorist attacks, while the nationwide sale is hold on to Nov. 5.

The American flag is a tangible symbol of both the American people and the ideals of democracy and the rule of law embodied in the U.S. Constitution.

The 50-star flag became the official flag of the United States of America on July 4, 1960, with the addition of Hawaii as the 50th state. All other versions of the flag ever in use are still legal, but they yield precedence to the 50-star flag when they are displayed together. The 50 white stars represent the 50 states admitted to the Union. The use of five-pointed stars, or pentagrams, symbolizes a break with European heraldic tradition wherein stars are normally six-pointed, or hexagrams. The near simultaneous admission of multiple states meant that there never were official flags showing 14, 16, 17, 18, 19, 22, 39, 40, 41, 42, or 47 stars. The 13 stripes stand for the original 13 states admitted to the Union. From 1795 to 1818, the flag had 15 stripes, one for each state then in the Union. In 1818 the flag reverted to 13 stripes as the addition of more stripes for new states became unwieldy. The white of the stars and the alternating white stripes stand for purity and innocence. The blue of the field on which the stars repose (the canton) represents justice and integrity. The red of the alternating stripes stands for hardiness and valor.