Which factor is considered a political external Thread of Continuity?

Military alliances are considered a political external Thread of Continuity because they represent the formal agreements and collaborations between nations or states to provide mutual support and security. These alliances influence global politics and can affect everything from military engagements to trade agreements. They are integral in shaping international relations and continuity in political strategy, as they often remain stable over time, contributing to a sense of security and predictability in the geopolitical environment.

While social order, geographical boundaries, and cultural heritage can influence political dynamics, they do not specifically embody the concept of continuity in the way that military alliances do. Social order relates more to internal societal structures, geographical boundaries can change due to conflict or negotiation, and cultural heritage pertains to shared traditions and values rather than formal political agreements.