I'm wondering why are babies vaccinated against whooping cough when they are a few months old?

To avoid death: The newborn will not develop protective antibodies to whooping cough if immunized at birth & maternal antibodies are usually weak. However, it begins to have that ability by 6-8 weeks when the first vaccine is given.Whooping cough fatalities are >60% in infants under 6 months of age.The young can develop progressive respiratory distress & cough hard enough to have a stroke.You shouldn't wait.