World War I saw the rise of the submarine and the airplane as vital weapons of war, and even now they remain keystones of military might. The airship, on the other hand, became little more than a means of capturing fantastic aerial shots at the Super Bowl.
Although the zeppelin was embraced by both the Germans and the Allies during World War I, the Germans made far more extensive use of the rigid, hydrogen-filled airships. The concept of "strategic bombing"—targeted airstrikes on a particular location—didn't exist before the conflict. The advent of aerial warfare changed that, and also robbed the British of the protection afforded by the English Channel. The zeppelin allowed Germany to bring the war to the English homeland. Kind of.
The airships of the era were in some ways more more capable than fixed-wing aircraft. They could fly higher, and farther, with greater payloads. But aerial raids were tricky. The large and slow airships flew at night and at high altitude to avoid being hit by artillery.