America is a nation with both ideal and passion. The political ideals of liberty, equality and selfgovernment have become the founding spirit forming the pillars for political identity, which makes America what it is. However, the various elements of the American founding spirit do not constitute a harmonious organism. These elements have deeprooted tensions and contradictions, which have existed in American politics ever since the founding period. With the development of productivity and the change of social formation, the inherent contradictions among the various core elements of the American founding spirit have also unfolded, exerting great pressure on American political structure in specific periods. To meet external economic, political, social and cultural challenges, the American political formation has evolved accordingly. Along this line, a research agenda on American politics can be established.