Alfredo Kindelán considers that both Guernica and Durango were "practice drills" in the development of more effective bombing strategies to use in bombings of Madrid. The city suffered a similar attack prior to the bombing of Guernica, and further attacks afterwards. Madrid presented a fierce resistance against the National troops that surpassed all of Franco's expectations and forced him to completely modify his attack strategy. A series of air bombings to demoralize the population were ordered both before and after Guernica.