美国在成立以来的二百多年中 ,它在世界范围内一直发挥着其举足轻重的作用 ,尤其是在当代 ,它的影响几乎涉及了社会经济、政治、文化等领域的各个方面。虽然美国的历史很短 ,但其发展速度之快 ,影响力度之大是有一定的历史根源的 ,它从建国伊始就经历了各种艰难、曲折的发展历程 For more than two hundred years since the founding of the United States, it has played a pivotal role in the world. Especially in the contemporary era, its influence has touched almost all aspects of socio-economic, political and cultural fields. Although the history of the United States is very short, its rapid development and great influence have its historical roots. Since the founding of the PRC, the United States has undergone various difficult and tortuous developments