Did Americans at the time really think Japan was weak and would not do anything?
Short answerYes; that assumption was widespread and contributed to American complacency before Pearl Harbor.
NotesA viewer asks whether Americans genuinely regarded Japan as weak and unlikely to act. The emphatic answer is that many did. The Washington treaty discussion provides the larger setting for that confidence. Racial prejudice and formal treaty superiority distorted assessments of Japanese naval aviation and political resolve.