The Centres of Disease Control and Prevention in the USA (CDC) defines Community immunity or Herd Immunity as "a situation in which a sufficient proportion of a population is immune to an infectious disease (through vaccination and/or prior illness) to make its spread from person to person unlikely. Even individuals not vaccinated (such as newborns and those with chronic illnesses) are offered some protection because the disease has little opportunity to spread within the community."
So even if our non-live vaccinations don't work that well and we aren't able to have live/attenuated vaccines, if those we interact with have been vaccinated, we are also protected.
The article below describes the relevance of Herd Immunity, what characteristics an infectious agent should have to make it possible to eradicate forever (for example smallpox) and how these same characteristics influence the protection provided by vaccination and what percentage of the community needs to vaccinated to protect those not vaccinated via Herd Immunity:
sciencebasedmedicine.org/he...
Neil