It wasn't strictly "oil" that was the only driver.

Japan was an Imperialist power that envisioned itself as having a series of both Japanese occupied and owned territories carved out of China and former European colonies, along with a series of satellite countries (Manchuko, but also see the "home" rule elements in the Philippines and similar puppet regimes).

In this regard Japan saw conflict with the US as inevitable in the long term, as it had designs on both the Philippines and Guam (and to a lesser extent smaller outlying locations like Wake).

Oil became a more immediate driver though as the US embargo threatened the Japanese mainland conquests. Also the earlier border clashes with the Soviets while not totally discouraging the eventual Japanese designs on Siberia* did make a "short" naval war with the US more attractive (and also the IJN was by and large available to conduct action in the Pacific, while the IJA was largely committed to China).

So in that regard the need for oil simply became a reason to execute the Pacific phase of the Japanese national aims vs the one and only reason Japan became involved in the pacific.

*I just have to add this caveat in, there's often an attempt to describe Khalkhin Gol as decisive, in effect having scared the Japanese away from ever taking action against the Soviets. More accurately the Japanese simply tabled operations against the Soviets until they'd sorted out the Pacific fighting/China more.