We have been neglecting the most effective way to prevent catastrophic disasters—by reducing their potential impact. Our current methods of prevention, remediation, and recovery are inadequate, primarily due to the limitations of our organizations and political system. To address this issue, the size of vulnerable targets should be reduced rather than trying to improve our ability to respond to disasters.

Several examples of growing vulnerabilities, such as the increasing population density in disaster-prone areas, the concentration of hazardous materials, and the expansion of critical infrastructure. Interconnected systems, like the electric power grid and the internet, become more vulnerable due to their concentration. Additionally, the widespread use of the Windows operating system in critical institutions makes them susceptible to cyberattacks.

Our pursuit of growth and affluence has contributed to these vulnerabilities and we must consider downsizing and reducing concentrations of risk to enhance our overall safety. For instance, a smaller city than New Orleans could still meet economic demands while being better protected from natural disasters. Miami is vulnerable to hurricanes and there is a need for better evacuation routes and building standards.

Complex systems are more vulnerable to catastrophic failures because the interactions between multiple components can lead to unexpected and cascading failures. This complexity is especially problematic when dealing with disasters caused by natural events, industrial or technological failures, or terrorist attacks. To address the challenges posed by complex systems, modularization is needed. Modularity involves breaking down a system into discrete modules or components, which reduces the potential for unexpected interactions and tight coupling between parts. Modularity offers several benefits:
- Improved Reliability: Modularity simplifies testing and troubleshooting, making it easier to identify and isolate issues when they arise. It allows for more graceful handling of failures, where a module can be replaced or substituted without disrupting the entire system;
- Comprehensibility: Operators and users find modular systems easier to understand and manage because they can compartmentalize functions and identify modules more clearly;
- Innovation: Modular systems promote innovation, as individual modules can be improved independently, and the benefits of innovations accrue to the responsible unit. This incentivizes creativity and efficiency.
In contrast to modular systems, integrated systems have tightly interwoven features and may exploit multiple uses. While integrated systems might be simpler to design initially, they can become more prone to unexpected interactions, reducing reliability and innovation incentives.

Commercial systems may resist modularity because it allows for competition, and integrated designs can capture more profits. Modularity remains a valuable approach, particularly in reducing the complexity and vulnerabilities of complex systems.

Microsoft's tendency to tightly integrate features into its operating system Windows is criticized for increasing complexity and vulnerability. When new features are tightly integrated, they become harder to uninstall and can lead to more significant consequences in the event of failures or security breaches. Microsoft integrates new features to gain market share and prevent competition. This approach increases complexity and can make systems more vulnerable to attacks or failures. Tight integration can make software systems more susceptible to security breaches, as a flaw exploited by malicious hackers or terrorists can have widespread consequences when integrated tightly into an operating system. Microsoft's dominant position in the software market allows it to pursue integration without significant competition. This lack of competition can hinder innovation and lead to less secure and reliable systems. Modularity, where software features are offered as add-ons rather than tightly integrated, can improve security, reliability, and innovation. Modularity allows for easier testing, troubleshooting, and substitution of components. Microsoft's approach is evolving, with some indications of a shift towards modularity. For instance, Microsoft's Chief Technical Officer, Ray Ozzie, has advocated for unbundling Office products and offering them online, emphasizing the importance of modularity and open competition.

The Internet is an example of a modular system that has exhibited high reliability, innovation, and security. The ability to plug in and play compatible programs (modules) has allowed for interoperability and reduced unexpected interactions. Despite attacks and vulnerabilities in individual components, the overall Internet structure remains reliable and secure.
The electric power grid experienced a decrease in reliability after industry deregulation and consolidation. The power grid, once composed of independently owned and regulated generating stations (modules), became tightly coupled due to increased power wheeling and industry concentration. This consolidation reduced modularity and negatively affected reliability and consumer costs.

Terrorist networks have a modular structure with autonomous and expendable cells. This modularity allows for quick innovation and reduces complexity. But there are forces within these networks that seek consolidation and control from the top, which can increase complexity and the potential for failures.

Disaggregating populations and systems is beneficial to reduce complexity, tight coupling, and vulnerability. Disaggregation and modularization not only reduce the damage caused by disasters but also promote innovation, flexibility, and a more equitable distribution of wealth. The evidence for the increase in industrial disasters and terrorist attacks is briefly discussed, highlighting the importance of addressing these issues through modularity and disaggregation.

Perrow, C. (2008), Complexity, Catastrophe, and Modularity, in: Sociological Inquiry, Volume78, Issue 2, May 2008, Pages 162-173.