<p>The Taiwan Strait has become a central flashpoints in contemporary great-power competition. This study examines the drivers of China’s escalating military incursions near Taiwan by analyzing the interaction of system-level structural shifts and unit-level domestic forces. At the system level, China’s assertiveness reflects its narrowing power gap with the United States and its efforts to contest U.S. influence, particularly during triggering events such as Pelosi’s 2022 Taiwan visit and Lai Ching-te’s 2024 presidential inauguration. At the unit level, the centralization of decision-making under Xi Jinping, rising nationalism, and economic pressures create incentives for risk-seeking behavior, reinforcing coercive policies toward Taiwan. The findings indicate that China’s military harassment fluctuates with both structural competition and domestic pressures, intensifying during politically sensitive moments and entrenching gray-zone tactics as a routine feature of its strategy. Although these dynamics have not yet converged into a critical war window, the accumulation of coercive measures and recurring crises has kept the risk of great-power war elevated and the trajectory of cross-Strait relations increasingly uncertain.</p>