The deaths of three firefighters in Colorado are casting a spotlight on the Trump administration’s creation of a new federal fire agency and its revival of a previously discredited policy to stomp out all wildfires quickly. One of the firefighters worked for the U.S. Wildland Fire Service — created in January without customary congressional approval by pulling personnel from four Interior Department agencies. The consolidation has sown confusion among some firefighters about who their bosses are and what their responsibilities should be. The administration’s focus on “full suppression” of new fires is a sharp reversal from a decades-long trend toward embracing flames as a tool to burn off fuel in the forest and lessen the risk of catastrophic blazes being stoked by a warming planet.