美国允许多重国籍的吗？ 美国入籍宣誓誓词

I hereby declare on oath that I absolutely and entirely renounce and abjure  all allegiance and fidelity to any foreign prince potentate state  or sovereignty of whom or which I have heretofore been a subject or citizen;  that I will support and defend the Constitution and laws of the United  States of America against all enemies foreign and domestic; that I will  bear true faith and allegiance to the same; that I will bear arms on  behalf of the United States when required by the law; that I will perform  noncombatant service in the Armed Forces of the United States when required  by the law; that I will perform work of national importance under  civilian direction when required by the law; and that I take this  obligation freely without any mental reservation or purpose of  evasion; so help me God.

我在这里郑重宣誓：完全放弃我对以前所属任何外国亲王、君主、国家或主权之公民资格及忠诚，我将支持及护卫美利坚合众国宪法和法律，对抗国内和国外所有的敌人。我将真诚效忠美国。当法律要求时，我愿为保卫美国拿起武器；当法律要求时，我会为美国做非战斗性之军事服务；当法律要求时，我会在政府官员指挥下为国家做重要工作，我在此自由宣誓，绝无任何心智障碍、借口或保留，请上帝帮我。

美国允许多重国籍的吗？