Short answers, pulled from the story.
Carl von Clausewitz (1780-1831), considered the father of Western modern strategic studies, defined military strategy as "the employment of battles to gain the end of war." He also famously argued that war is "the continuation of policy by other means," placing political aims above purely military goals.
Military strategy involves using military resources against an opponent's resources to gain supremacy or reduce the opponent's will to fight. Grand strategy, sometimes called national strategy, is broader: it encompasses the overarching direction of the largest organizations, such as nation states or alliances, drawing on diplomatic, informational, military, and economic resources simultaneously.
Sun Tzu (544-496 BC) is generally considered the father of Eastern military strategy. His text The Art of War defined 13 principles and influenced war tactics in China, Japan, Korea, and Vietnam, and later found practical use in Western military and political affairs as well.
Eastern military strategy, rooted in the tradition of Sun Tzu, places greater emphasis on asymmetric warfare and deception. Western strategy has historically focused more on direct force and pitched battle. Chanakya's Arthashastra served a parallel role to Sun Tzu's text in Indian and Asian strategic thought.
The United States Army Field Manual FM 3-0 lists nine essential concepts: objective, offensive, mass, economy of force, maneuver, unity of command, security, surprise, and simplicity. Together they address how to concentrate combat power, protect against enemy advantage, and keep plans clear enough for forces to execute.
Netwar is a field of strategic thinking developed to address non-traditional adversaries such as Al-Qaeda, which operate as sparse networks without central coordination. Because these organizations lack a central authority defining their military and political strategies, standard strategic approaches designed for conventional hierarchical enemies are difficult to apply against them.