As our world becomes more computerized, security and privacy takes on a prominent role in allowing us to enjoy the benefits of new technologies without the risks. Addressing the new challenges that come with this role requires a change in how we approach and solve problems in computer security. My vision is that we must view computer security as a whole-system property ranging from the physical-layer right up to applications and end-users. In line with this vision, my approach to computer security involves formulating the right security problem to work on, addressing design-level issues by constructing strong defenses at the appropriate layer of abstraction, and challenging common assumptions to understand realistic threats. In this talk, I will give several examples of my approach and vision, focusing on emerging technologies that span the digital-to-physical interface. I will cover technical results at various level of abstraction, including analysis techniques that found exploitable design-level vulnerabilities in closed-source smart home platforms, a new design for trigger-action platforms that provides strong integrity guarantees, and an analysis of how realistic attacks on machine learning can occur in the physical world. Finally, I will share my vision of the future of security and privacy research in an increasingly connected world.