黨外運動
Hsu publicly supported Lien Chen and James Soong in the 2004 presidential election. In March 2004, Hsu and a dozen other prominent politicians involved in the Tangwai movement published "The Joint Declaration of the Tang Wai participants" (黨外人士聯合聲明, the joint declaration of the participants outside of the political party movement), in which they reprimanded Chen Shui-bian for betraying the ideals of democracy and freedom that they once pursued. Criticising Chen for being "corrupted by power" and close with Lee Teng-hui and black gold, Hsu and others urged voters who once supported DPP for its ideals not to vote for Chen, to give him a chance to "reflect on himself".