What was the main way in which imperialist nations protected their colonies and trade in the 1800s?

Imperialist nations primarily protected their colonies and trade in the 1800s through military presence and naval power. They established forts and stationed troops to deter uprisings and defend against rival powers. Additionally, they often negotiated treaties with local leaders to secure trade rights and access to resources, while using economic leverage to maintain control. This combination of military strength and diplomatic maneuvering helped ensure the stability of their colonial enterprises.