What I really mean is: From today's perspective, I think no country would decide to launch an attack to USA. They really thought they had a chance to win? Were they expecting other countrie's support?
You might like to read the Pearl Harbor section of the FAQ at https://www.reddit.com/r/AskHistorians/wiki/faq/militaryhistory/wwii/fronts#wiki_pearl_harbor
In the app, the # anchor doesn't work, so you have to look about halfway down the page for Pearl Harbor
This is intended as a starting point, not to discourage discussion. Further questions, info, and debate are welcome.