Digital Sovereignty must be on the agenda of every modern nation. Digital
technology is becoming part of our life details, from the vital essentials,
like food and water management, to transcendence in the Metaverse and Space.
Protecting these digital assets will, therefore, be inevitable for a modern
country to live, excel and lead. Digital Sovereignty is a strategic necessity
to protect these digital assets from the monopoly of friendly rational states,
and the threats of unfriendly Malicious states and behaviors. In this work, we
revisit the definition and scope of digital sovereignty through extending it to
cover the entire value chain of using, owning, and producing digital assets. We
emphasize the importance of protecting the operational resources, both raw
materials and human expertise, in addition to research and innovation necessary
to achieve sustainable sovereignty. We also show that digital sovereignty by
autonomy is often impossible, and by mutual cooperation is not always
sustainable. To this end, we propose implementing digital sovereignty using
Nash Equilibrium, often studied in Game Theory, to govern the relation with
Rational states. Finally, we propose a digital sovereignty agenda for different
country's digital profiles, based on their status quo, priorities, and
capabilities. We survey state-of-the-art digital technology that is useful to
make the current digital assets sovereign. Additionally, we propose a roadmap
that aims to develop a sovereign digital nation, as close as possible to
autonomy. Finally, we draw attention to the need of more research to better
understand and implement digital sovereignty from different perspectives:
technological, economic, and geopolitical