WASHINGTON (AP) — Japan’s Takata Corp. rejected federal regulators’ demand Wednesday for an expanded, nationwide recall of millions of air bags, setting up a possible legal showdown and leaving some drivers to wonder about the safety of their cars.Amid the standoff, Honda Motor Co. decided to act on its own and recall cars with the potentially defective equipment in all 50 states. But other automakers have yet to make a decision.At issue are air bags whose inflators can explode with too much force, hurling shrapnel into the passenger compartment. At least five deaths and dozens of injuries have been linked to the problem worldwide.Over the past six years, Takata and 10 automakers issued a series of recalls covering 8 million cars in the U.S., mostly in high-humidity areas such as the Gulf Coast, because of evidence that moisture can cause the propellant to burn too quickly.