But when World War One started they became weapons. Pilots could spy on enemy ... where poisonous gas was used for the first time, gas masks had to be created urgently to protect soldiers during ...

World War I continues to be an opportunity to look back at some of the fascinating and terrible weapons the United States ... the first mass-produced grenades used by the United States military.

675 * These weapons can deliver a unitary warhead or submunitions, but the U.S. Air Force has not indicated how many of each type were used.

Since the North Vietnamese Air Force only represented a threat to U.S. bombing raids in the north, not to American bases in the south, anti-aircraft weapons were not used frequently by U.S. forces.

But when World War One started they became weapons. Pilots could spy on enemy ... where poisonous gas was used for the first time, gas masks had to be created urgently to protect soldiers during ...