Until very recently, the Taiwan issue had become so quiescent that it was easy to forget that just a few years earlier Taiwan had been at the forefront of worries about a possible outbreak of conflict in East Asia. Under the leadership of Chen Shui-bian and his Democratic Progressive Party (DPP) during the period from 2000 to 2008, Taiwan pursued measures to increase its de facto independence from mainland China and lay the foundation for a more formal separation (Carpenter 2005; 81–99, 105–7). Beijing reacted harshly to Taipei's behavior, leading to a series of crises that alarmed the United States, Taiwan's protector, and led to a spike in speculations that the mounting tensions could lead to war (Carpenter 2005; Copper 2006).