Many US citizens wanted to remain neutral at the start of World War I primarily because they worried that too many Americans would die in combat. There was a strong sentiment among the American public to avoid getting involved in foreign conflicts, especially given the vast distances and the devastating loss of life associated with war. Additionally, many citizens were focused on domestic issues and believed that the United States should not entangle itself in the affairs of Europe.
While some Americans may not have fully believed in the cause of the Allied Powers and feared that the war could eventually spread to American soil, the predominant motivation for neutrality was the concern over the potential human cost involved in joining the conflict.