# Active Cyber Defence and National Strategy: Protecting Critical Infrastructure

How national cyber strategies and active defence programs work together to protect the infrastructure that societies depend on, and what it means for organizations operating within it.

Critical national infrastructure, power grids, water treatment, healthcare systems, financial clearing systems, transport networks, sits at a different risk tier than a typical business. An outage doesn't just cost money; it can put lives and social stability at risk. This is why governments increasingly pair broad national cyber strategies with active, hands-on defence programs rather than relying on individual operators to defend themselves alone.

 
## What a national cyber strategy actually contains
 A modern national cyber strategy typically sets out several coordinated goals: raising the baseline security of critical sectors through mandatory standards, building government capability to detect and respond to large-scale threats, sharing threat intelligence[↗](/threat-intelligence) between government and infrastructure operators, and investing in the skills pipeline needed to staff all of it. The strategy is the "what and why", active cyber defence programs are the "how."

 
## What active cyber defence looks like in practice
  - **Automated threat takedown services.** Many national programs operate services that automatically detect and take down phishing[↗](/phishing) sites, malicious domains, and fraudulent content impersonating government or critical services, often before most citizens ever see them.
 - **DNS-level filtering and threat intelligence sharing.** Public sector and critical infrastructure operators can subscribe to services that block known-malicious domains at the DNS level and receive early warning of active campaigns targeting their sector.
 - **Vulnerability[↗](/vulnerability) disclosure and scanning programs.** Proactive scanning of internet-facing government and infrastructure systems, with responsible disclosure[↗](/responsible-disclosure) back to the operators, closes gaps before attackers find them.
 - **Sector-specific incident response[↗](/incident-response) support.** Dedicated response capability for critical sectors (energy, health, water, finance) that can be called on during a major incident, recognizing that a single organization's incident response team may be overwhelmed by a nation-state-level attack.
  
## Why critical infrastructure needs a different risk model
 Standard commercial risk management[↗](/risk-management) asks "what's the financial cost of this risk, and is mitigation worth the investment?" Critical infrastructure risk management has to also ask "what's the societal cost if this fails, even briefly?" This changes the calculus significantly, a control that wouldn't be cost-justified for a retail business (extensive redundancy, air-gapped backup[↗](/backup) control systems, mandatory incident reporting timelines) becomes standard practice when a failure could affect hospitals, water supply, or the power grid.

 
## Operational technology: the added complexity
 Much critical infrastructure runs on operational technology (OT), industrial control systems, SCADA, and similar systems that were often designed decades ago with no expectation of ever being internet-connected. Bridging OT and IT security is one of the hardest problems in the field: patching a legacy control system can be riskier than the vulnerability it fixes, since an untested patch[↗](/patch) might cause the very outage security is meant to prevent. This is why network segmentation[↗](/network-segmentation), rigorous change control, and close collaboration between engineering and security teams matter more here than almost anywhere else.

 
## What this means for organizations in these sectors
  - Expect and plan for mandatory security baselines and incident reporting requirements, these are increasingly law, not best practice, for critical sectors.
 - Participate in sector information-sharing programs; threat intelligence about an attack on a peer organization is often the earliest warning you'll get.
 - Build relationships with national cyber authorities before an incident happens, not during one.
  
## Related reading
 [Critical Infrastructure and Active Cyber DefenceEnergy, water, healthcare, and transportation systems face security demands beyond typical organizations, and benefit from national-level active defence programs designed specifically for them.](/critical-infrastructure-and-active-cyber-defence) [Active Cyber Defence and National Cyber StrategyBeyond individual organizations, governments run large-scale programs to reduce cyber harm across entire countries. Here's how active defence and national strategy fit together.](/active-cyber-defence-and-national-cyber-strategy) [Supply Chain Security: Protecting Your Vendors and PartnersA growing share of major breaches start with a trusted vendor, not the target organization itself. Here's how to think about supply chain risk practically.](/supply-chain-security-protecting-your-vendors-and-partners)