Analysing why a nation resorts to warfare usually takes a little more analysis, which is why we also need to look at the strategic situation. Thus! Here are some previous answers for your consideration:

• u/jschooltiger goes into the direct reasons for attacking Pearl Harbor;
• which also links to u/ParkSungJun's analysis on why Japan was undergoing a resource shortage and thus why they thought attacking the US was a good idea;
• and u/Starwarsnerd222 also goes into Japan's political and strategic situation at the time.

As ever, more can always be said, so if anyone else would like to address the question, please don't let this post stop you!