The US-Israeli war with Iran has put Japan's relationship with US President Donald Trump at a significant stress test. This comes as Japan's vulnerability in national security - energy dependence. The country imports over 90% of its crude oil from the Middle East, a crucial issue for Japan. Fuel prices have already reached multi-year highs and Tokyo has begun tapping strategic oil reserves to stabilize supply, prices, and public sentiment. However, pressure from Washington is mounting, with Trump's messaging inconsistent. In practical terms, Japan is unlikely to commit combat forces due to its pacifist postwar constitution, but any meaningful military involvement in a US-led conflict would face legal and political barriers. The dilemma for Japan is acute as its security environment is at its most severe in decades.