In a state long accustomed to the weight of its own scale, California has reached for a quiet but consequential lever — adjusting the very composition of the fuel its millions of drivers burn each day. By approving year-round sales of E15, a gasoline blend carrying 15 percent ethanol, state leaders are acknowledging both the limits of their power over global oil markets and the obligation to act within those limits. The decision, shaped by geopolitical disruption abroad and economic strain at home, may prove less a final answer than a first draft of a broader national conversation about how de