In 1915, World War I was raging in Europe, Africa, and Asia. Safe behind two oceans, most Americans did not feel threatened by the conflict, but William Boeing was one of a growing segment of the U.S. population that advocated "preparedness." Fourteen men and five women had formed the Aero Club of the Northwest in the Ladies' Annex of the University Club on August 24, 1915. William Boeing was elected president. From that point on, he was an ardent advocate for National Preparedness. He was also interested in the ideas of Henry Woodhouse, editor of Flying magazine, who had written, "With 5,000 aviators, this country would be in the position of the porcupine, which goes about its daily pursuits, harms no one, but is ever ready to defend itself."
In November 1915, Boeing spent a busy week in his new "hydroaeroplane." With test pilot and mechanic Herb Munter as his passenger, the lumberman flew to Tacoma and back to Seattle. He dropped cardboard "bombs" on a crowded California-Washington football game at the University of Washington to prove that Americans were vulnerable to foreign attack. One of the cardboard messages read: