Final answer:
Protective measures designed to safeguard information systems are known as security controls, security safeguards, or countermeasures. These are essential for upholding aspects of national security, which now includes not only military but also economic, environmental, and computer network security.
Step-by-step explanation:
Protective measures prescribed to meet the security requirements (i.e., confidentiality, integrity, and availability) specified for an information system are known as security controls, security safeguards, or countermeasures. These terms are generally synonymous and describe the various methods and strategies employed to protect the information and operations of an information system from unauthorized access, use, disclosure, disruption, modification, or destruction. Such measures may encompass a range of strategies, including advanced technological tools like two-factor authentication, personnel security protocols, and various forms of security management.
Policies and measures to ensure national security have evolved over time, moving beyond military might to include a broader perspective that incorporates economic security, environmental security, and resilience against different kinds of threats, including cyber threats, natural disasters, and environmental events. One aspect of such security includes civil defense and emergency preparedness measures, such as anti-terrorism legislation and ensuring the resilience of critical national infrastructure. Modern national security strategies also emphasize political stability and the enforcement of policies via diplomatic and economic channels in addition to military capabilities.