Payments to social security recipients, the costs of national defense, medical expenditures, and interest payments on the national debt constitute the bulk of federal government spending. (educationworld.com)
Just to give a concrete example, for instance I don't understand why belief in strong national defense has to go hand in hand with being anti abortion and anti gay marriage. (politics.stackexchange.com)
Security clearance opens up numerous opportunities, often involving advanced technology, with commercial and government organizations involved in national defense, homeland security, and related fields. (sciencemag.org)