YES: Countries should aim to be fully or extensively self-sufficient in some ways as doing so advances their interests significantly in an unpredictable world.
Militarily, countries today should aim at high levels of self-sufficiency in the design, development and deployment of defense technologies relevant to their national security to prevent dependency on unreliable external parties which compromise their deterrence capabilities.
Economic security in some countries are based on clear access to strategic resources such as water and energy, making it imperative that they produce or develop such resources extensively on their own.
For some countries with modest economic goals, self-sufficiency is more achievable and they may want to pursue it extensively if it contributes significantly to national outcomes and well-being based on non-material considerations, such as environmental sustainability and social equitability.
NO: Countries should aim to be self-sufficient in a limited way as the gains from participating in an interdependent and integrated world are much more significant in comparison to isolation.
Given their complex features and operations, efforts to attain full self-sufficiency in defense technologies are economically ruinous for many countries, and most would fare better if they work towards a moderate level of self-sufficiency by purchasing equipment and hardware from trusted allies.
The geographical constraints faced by many countries prevents them from attaining full self-sufficiency in vital natural resources, making it more viable for them to trade such resources with each other in a reciprocal and fair way.
For most countries today, economic growth is based on international trade, economic diversification and the expansion of consumer choices, making full self-sufficiency an impractical goal that no country should willingly undertake.